In early December, Mark Melancon, Aroldis Chapman, and Kenley Jansen inked baseball’s three all-time richest contracts for late-inning arms. Absent comparably elite starting pitching talent on the free-agent market, the Boston Red Sox assembled a trade package that included Yoan Moncada, arguably baseball’s top prospect, for Chicago’s Chris Sale, who has finished no worse than sixth in the AL Cy Young voting over the past five seasons.

The cost in dollars and prospects for three of the game’s best closers and one of its best starters reinforced what the regular season and postseason had already demonstrated: Impact starting pitching is in short supply these days.

In October’s four division series, starting pitchers posted a combined 5.36 ERA over their 30 starts — only half of which lasted five innings. Even in the LCS, where starters posted a combined 2.71 ERA, only four starters completed at least seven innings. The World Series cemented the growing trend: In the seven-game Fall Classic, no starter completed more than six innings in a bullpen-dominated showdown. While managers have the luxury of using their relievers in particularly extensive and uncommon ways in the playoffs, the patterns underscored the recent changes in baseball’s starting pitching landscape, which has become alarmingly fraught with injury and ineffectiveness.

That’s not to say that none of the game’s finest pitchers delivered excellent seasons in 2016. Sale, Madison Bumgarner, Johnny Cueto, Jon Lester, Justin Verlander, Corey Kluber, and Cy Young Award winners Max Scherzer and Rick Porcello met or exceeded general expectations. Missing from that group was baseball’s brightest star, Clayton Kershaw, who spent more than two months on the DL.

Baseball’s starting pitching club had already grown crowded and diluted over the past three years, averaging nearly 300 unique starting pitchers per season, but with instability further creeping into the upper crust, that club has begun opening its doors to more members than ever before. That’s not because bouncers’ pockets are lined with twenties, though: It’s because teams have no choice. The 2015 season set the record for the most individual pitchers to start at least one major league game, at 313, and that’s proved to be no fluke. The 2016 tally hit 310, the second most ever, and a total that likely would have climbed higher had both wild-card races not required all 162 games to determine winners, forcing the playoff hopefuls to start their best bets instead of clearing the way for youngsters and swingmen to eat some innings or audition for 2017 roles.

I spent 10 years in baseball operations departments, beginning with the San Diego Padres in 2005 and continuing when I joined the Arizona Diamondbacks prior to the 2011 season. With both franchises, I was often involved with the daily management of the 40-man roster and later managed the pro scouting department. Most recently, I was a pro scout for the Tampa Bay Rays. Every phase of the scouting process is a passion of mine.

As such, when I noticed in early May that presumptive aces like David Price and Zack Greinke were dealing with ineffectiveness (and later injury), I thought about some of the late-night conversations and debates with scouts and other colleagues that I’d had in places like the winter meetings. We were always looking to improve our starting pitching, and we often asked each other: Who is the starting pitcher you’d want on the mound in Game 7 of the World Series? The question now appears to be: Who is the relief pitcher you’d want to hand the ball to in the seventh inning of Game 7? Starting pitching has fallen off so steeply that teams are doing whatever they can to lessen a starter’s responsibility.

Amid baseball’s increasingly saturated and ineffective starting pitching landscape, it’s easy to confuse a no. 1 starter with an ace. Pitchers who don’t possess the skill of, say, Kershaw, are still being paid as if they’re elite because demand is exceeding supply, but they’re failing to validate their salaries through performance. This offseason, Rich Hill, who will be 37 when he takes the mound in 2017 and has made only 24 starts over the past two seasons, signed a three-year, $48 million deal. Baseball’s arms race is shifting to the pen, and starters with questionable medical records are cashing in, because the MLB ace is increasingly vanishing from the game.

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What Is an Ace?

Before we can determine why the MLB ace has become such a precious commodity, we must first define what an ace is. Not very long ago, the game was flush with them: As Greg Maddux, Randy Johnson, Pedro Martínez, Mike Mussina, and Curt Schilling were nearing the end of prolonged stretches of excellence, Roger Clemens forged on, and a pair of Roys (Halladay and Oswalt) were on the brink of dominating. In 2002, four pitchers averaged 7.0 or more innings pitched per start and posted an ERA of 3.00 or less: Halladay, Tim Hudson, Johnson, and — wait for it — Bartolo Colón. (Substitute FIP for ERA, and Hudson and Colón fall off, while Schilling enters.)

Chris Carpenter, Johan Santana, and Brandon Webb bridged the gap to the most recent decade, where the still-active Félix Hernández, CC Sabathia, Verlander, and Adam Wainwright emerged as aces, while Halladay continued his dominance and welcomed ace teammate Cliff Lee.

While those pitchers share certain statistical markers, they also share something intangible. Identifying an ace isn’t always scientific; it’s also about feel, the marriage of perception and reality brought on by sustained dominance. Certain accomplishments and thresholds help define the standing, but there are no absolute requisites. It’s as much about reputation and attitude as it is about fastball command and complete game tallies.

Of course, there are certain established thresholds: When he takes the ball, an ace will typically pitch effectively into the seventh inning or later, and he will take the ball consistently every fifth day, resulting in 220-plus innings on the season. He will accrue close to one strikeout per inning because he has the ability to effectively locate swing-and-miss stuff.

An ace will have plus command and control of his fastball, which will generally average at least 92 mph and often flash, if not sit at, 95 or better. He’ll also feature above-average secondary pitches (generally a slider or cutter, a curveball, and a changeup) that often “play up” (yielding results better than what that pitch would net on its own or when complemented by a lesser fastball). An ace will overcome a shortcoming, if he has any at all, with plus-plus ability elsewhere or the general feel and pitchability to mask it. Part of the ace’s advantage is that he creates an uncomfortable at-bat through velocity, angle (think Bumgarner or Sale vs. a left-handed hitter), deception, and/or intimidation.

An ace also has the ability to dominate a game over — and this is where the term gets tricky to define — an established period of time. How long is enough? Well, it depends. My wife likes to suggest that our infant daughter might need a diaper change, but she’s “not sure.” My response: You’ll be sure when she needs one. The same goes for identifying an ace: You’ll be sure. If you have to ask, a pitcher isn’t an ace.

Across MLB in the 2016 regular season, when a starting pitcher completed at least 7.0 innings, his team won 72.5 percent of the time. When a starter goes deeper into a game, he allows his team to bypass the weaker middle relievers (a corps that is largely displaced in October but essential in the regular season) and turn directly to the best bullpen arms, and the numbers show that registering those extra three outs really matters: In 2016, when a starter went at least six innings but less than a full seven, his team’s chances of winning dropped to about 56 percent. The 2001 Mariners won 116 games, playing at a .716 clip; that winning percentage is essentially on par with the success teams enjoyed last season when their starters went at least seven innings. That’s exceptional baseball, but it’s also rare: In 2016, just 23 percent of all starts lasted at least seven innings.

Consistency inning to inning and game to game matters, and consistency season to season does, too. When distilling WAR into everyday baseball lingo, FanGraphs defines a starting pitcher with between 5 and 6 WAR for the season as a “superstar,” and it assigns MVP quality to a player producing a single-season WAR of 6 or more. Since 2007, an average of 10 pitchers per season have posted a WAR of at least 5; in 2016, nine pitchers (Kershaw, Noah Syndergaard, the late José Fernández, Scherzer, Cueto, Porcello, Verlander, Sale, Kluber) reached or crossed that boundary. The pitchers who have been able to repeat such seasons, however, can be counted on one hand: In the past three seasons, only Kershaw, Kluber, Sale, and Scherzer have eclipsed the 5.0 WAR threshold annually. Kershaw’s run goes back to the 2011 season, and Scherzer’s streak is now at four years. Looking back over the past 10 seasons, Kershaw’s stretch of six consecutive seasons of a WAR of 5 or more is matched only by Cliff Lee, who posted such numbers from 2008 to 2013. Sabathia and Halladay both accomplished the feat from 2006 to 2011. Verlander tallied four consecutive years from 2009 to 2012, then hit the mark again in 2016. Hernández notched the necessary total in five of six seasons from 2009 to 2014 (missing in 2011). That’s rare air.

From a scouting perspective, an ace will most likely possess above-average pitches and tools across the board. Scouts give each pitch — in addition to tools like command, control, and deception — a grade on the 20–80 scale, in which 50 represents the major-league average, 60 marks an above-average or “plus” tool, and 30 represents a tool that is well below average. While the exact terminology for classifying a player’s overall value varies from team to team, aces will universally string together 70s and 80s.

Scouting reports alone do not make an ace, though. Plenty of guys have had the stuff, and many have even shown it in spurts. But for a pitcher to establish himself as an ace, he has to demonstrate that dominance on the field over the course of enough innings, and seasons, to solidify his standing among peers, front-office officials, media, and fans.

Shifts in the Pitching Landscape

This past season, fewer pitchers than ever upheld those ace results and reputations. As stated, the number of unique starters in 2016 was topped only by the figure from 2015. Meanwhile, the number of starters logging 220 innings is dwindling: During the 2016 regular season, only six pitchers eclipsed that mark, and only nine total cracked 210 IP. Only five pitchers reached 220 innings in 2012, a record low for non-strike-affected seasons. The large dip was a sign of things to come; over the past five seasons, no more than eight starters have logged 220 innings in a single season, and the 2016 season also set the record low for reaching the 210-inning threshold. Unsurprisingly, the amount of 200-inning pitchers reached its nadir this past season as well, with only 15 pitchers breaking through.

While innings pitched does not correlate directly to results, it is a strong indicator of success and durability. The 2016 numbers bring to mind work stoppages and war years. Similarly, only 17 qualified starters averaged 100 or more pitches per start in 2016; there were only 21 such pitchers in 2015, and unsurprisingly, those two totals are the two lowest of the 21st century. The next-lowest total was 31 in 2006. Starts are more abbreviated today because of both greater scrutiny on managers’ handling of pitching staffs and research demonstrating the success of hitters against a pitcher the third time through the lineup, but the upshot is fewer aces, because there’s less of a desire to foster the development of a workhorse.

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In the four-year span of 2008 to 2011, there were 16 instances of a qualifying starting pitcher averaging 7.0 IP or better per start with an ERA of 3.00 or lower (using FIP, the occurrences decrease to nine). Ten different hurlers accomplished the feat, with Halladay breaking the threshold in all four seasons. (Incredibly, Halladay tallied 35 complete games over 130 starts in that span — a CG more than once every four times out!) The group also included Hernández, Lee, and Sabathia, each of whom hit the mark twice, and Kershaw, Verlander, Tim Lincecum, Ricky Romero, James Shields, and Jered Weaver.

Over the next four years (2012 to 2015), seven starters combined to reach the mark 10 times: Kershaw, three times; Wainwright, twice; Cueto, R.A. Dickey, Dallas Keuchel, Lee, and Verlander. (Using FIP, there are still 10 occurrences, but with Price and Hernández replacing Cueto and Dickey.)

Not a single pitcher achieved the feat in 2016 (though Kershaw would have if he’d totaled enough innings to qualify). The dominance is disappearing.

The adage used to be that a team needed eight starters to make it through a season. Today, a team might need a dozen to have a chance, and almost certainly will need close to 10. The attrition rate of starting pitching is at an all-time high in part because of a variety of injuries that force replacement pitchers into major-league action before they’re ready to compete at that level. There is no single clearinghouse that accurately tracks all instances of UCL reconstruction, better known as Tommy John surgery, from the high school ranks through MLB, but according to data from Jon Roegele of The Hardball Times, there were 105 TJs performed in 2012, 100 in 2013, 134 in 2014, and 128 in 2015. The cases of TJ dropped to approximately 85 in 2016, a significant shift, though perhaps deceptively low due to reporting delays at the sport’s lower levels.

Even if TJ cases really did significantly decline, overall disabled list placements for pitchers increased to approximately 307 in the 2016 season. (The DL count does not include transfers from the 15-day DL to the 60-day DL, nor does it account for repeat DL placements for the same injury. All DL figures are approximate because some placements result from injuries in the prior season, and not all are recorded identically.) Of the 2016 DL placements, 170 were arm related, and 82 of them were elbow or forearm related. In 2015, there were 278 DL placements for pitchers, and 167 of them were because of an arm injury, with 85 of those related specifically to the elbow or forearm. In 2014, there were 238 pitchers placed on the DL, and in 2013, there were 255.

There’s inherent value in accounting for injuries beyond just Tommy John surgery. Aside from lower body and core injuries, it’s essential to account for other elbow injuries, like incomplete tears of the ligament that are treated with platelet-rich plasma injections as an attempt to heal without surgery. There are also the bone spurs that ended Steven Matz’s season or the strained flexor mass that put an end to Stephen Strasburg’s breakout campaign. The more damning shoulder injuries — tears of the rotator cuff and labrum — are not romanticized or naively assumed to be routine, like Tommy John. Shoulder injuries are decreasing, but are nonetheless career-threatening. Thoracic outlet syndrome is a rare yet severe condition that ended Matt Harvey’s disappointing 2016 season prematurely, and has taken time from Carpenter, Jaime García, and Tyson Ross, to name a few. In other words, it’s a good time to be a healthy man who can throw the ball 60 feet and 6 inches downhill.

The current collective bargaining agreement, agreed upon at the end of November, introduced a 10-day disabled list that should benefit overall pitcher health. Whereas a trip to the erstwhile 15-day DL could cost a starting pitcher with a minor injury three starts, the 10-day variety enables a club to shut down its injured pitcher and — with the presence of an off day during the stint — cost him only one start. The borderline DL candidate who generally pitches through a nagging injury and fights a trip to the DL will now be much better positioned to rest, recover, and return healthier. This five-day adjustment has the ability to yield thousands of healthy starts.

Meanwhile, as more and more cash is infused into the game, the free-agent structure represents a nonlinear relationship between talent and compensation, skewing the view of today’s pitchers. The highest-paid pitchers are often not the very best, but more likely the most recent to have reached the open market. The instinct to correlate salary to talent can be as misleading and deceiving as Hernández’s 13–12 record in 2010. Newly forged television deals have made Vegas whales out of some unlikely franchises — who would have thought that the Diamondbacks would outbid the Dodgers for Greinke’s services last offseason? — and teams’ needs are never the same across the league or across seasons.

What’s more, home run rates and strikeout rates are both at a high for the century. Power pays, and an all-or-nothing approach rewards many hitters whose slugging percentage masks tremendous contact issues come contract time. Chris Davis led all of baseball in both homers and whiffs in 2015, his contract year, and he was rewarded with a seven-year deal worth $161 million. Because hitters no longer feel shame in striking out, they no longer adopt a two-strike approach, “shortening up” to sacrifice power for contact. This mental approach, whether intentional or not, neutralizes one of the greatest weapons a pitcher possesses: the threat of the K. Scherzer led the majors in strikeouts in 2016 — and for a while also ranked among the NL leaders in homers allowed. Though he coughed up just 10 long balls across 100.2 innings in the second half, he surrendered homers to an uncanny 20 different batters (from Freddie Freeman to Martín Maldonado) in the first half.

Away from the field, traditional media, bloggers, and tweeters set unrealistic expectations that hang over prospects before they reach the big leagues, let alone arbitration. The New York Mets’ big three of Jacob deGrom, Harvey, and Syndergaard were a huge part of the team’s 2015 NL pennant run and 2016 World Series hopes. Well before any injuries derailed the 2016 campaigns of Harvey or deGrom, though, external comparisons to Glavine, Maddux, and Smoltz — three men who rode the ace mantle and their ace stuff all the way to Cooperstown — positioned the Mets’ young stars with seemingly only one way to go: down. Outcomes aren’t decided by sound bites, nor do expectations generate end-of-season hardware. Aces do their talking on the field.

Establishing Ace Status and Separating Pretenders From Contenders

In May, the Dodgers played a 17-inning game during which all but one member of the pen appeared, as did the pitcher scheduled to start two days later. Four arms in the pen had thrown on consecutive days, with two of them having thrown in three straight. At 7:10 p.m. in Dodger Stadium on May 23, the night after the marathon victory, Kershaw took the ball.

Two hours and 11 minutes later, he had pitched his team to a 1–0 victory. He didn’t have his best stuff, but he delivered a 102-pitch, complete-game two-hitter, relieving an exhausted bullpen and providing a welcome reprieve for a sluggish offense.

The majority of starts and games over the course of the season don’t take on extra meaning like that start did for Kershaw and the Dodgers. When one does, however, the teams fortunate enough to boast an ace hope he’s on the mound, and the teams that lack an ace can only wish they had one. Few teams can enjoy what the Dodgers did: nine innings of unrelenting competitiveness, hustle, and desire; excellent command of three plus pitches; and the ability to impart confidence among teammates.

Kershaw’s total WAR since 2013 (29.9) is 28 percent higher than the next-best pitcher’s (Scherzer) in that span. Despite not throwing a single pitch in July or August 2016, he still led all pitchers in WAR until the final days of his DL stint. After briefly relinquishing the lead, Kershaw ultimately tied with Syndergaard for the top WAR, securing a share of the WAR title for the fourth consecutive year despite not reaching the requisite innings pitched to qualify for pitching titles in rate categories.

Kershaw is undeniably an ace. So is his division mate, Bumgarner. His postseason résumé (not limited to his mythical 2014) and consistent regular-season performance speak for themselves. Sale is an ace: He has quietly been the American League’s most consistent and dominant performer since 2012, and the haul the Red Sox gave up for him reflects how rare of a breed he now is. Scherzer signed an ace’s contract with the Nationals, and he has honored that agreement. Kluber’s past three seasons support the ace title statistically, and it’s an uphill battle to argue that the man who easily could have won two of the past three AL Cy Youngs is not an ace. The third season in that span, his 2015 campaign, is a textbook example of the perils of judging a pitcher only by wins and losses. The peripherals were still there, even if his winning percentage wasn’t, and his WAR over the past three seasons is second to only Kershaw’s.

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Kluber and Cy Young Award–winner Porcello had incredibly similar 2016s statistically, two of the biggest differences being wins and run support. Porcello averaged nearly two more runs per start, a key element in his 22 wins. The 2015 AL winner, Keuchel, did not factor into this past season’s Cy Young conversation. In fact, none of the top three pitchers in the 2015 AL vote (Keuchel, Price, Sonny Gray) received even one vote in 2016. Of the starting pitchers on the ballot, only Kluber and Sale received votes in each of the past two years. Porcello will have to buck the trend in 2017 to prove he’s not a one-year wonder with an ace’s paycheck.

“Be wary of the career year,” one of my favorite scouts likes to say. A pitcher doesn’t have to be an ace to produce statistics like one for a season. Numerous pitchers have won one Cy Young. Whether it’s Dickey, Jake Peavy, or Keuchel, their lack of consistency at the highest level doesn’t mean they’re not good pitchers — but it does mean they aren’t true aces.

This isn’t fantasy baseball. This isn’t a daily lineup competition. This isn’t the 22-year-old we all knew who bragged about the money he made trading stocks online during a slow afternoon at his day job.

Fernández certainly belonged in the conversation until tragedy struck. Syndergaard is undoubtedly developing into an ace, but with only about 80 more innings pitched in his major league career than Verlander registered in his Cy Young and MVP campaign of 2011, it’s irresponsible to confidently assign the tag to him yet. Syndergaard’s FIP and WAR are trending the right way, but while the Mets would certainly be correct to value him as an ace in a hypothetical trade discussion, he is at least one season of health and domination away from cementing his status as a bona fide ace in the game. He’ll enter 2017 expecting to log his first season of 200-plus innings pitched.

Jake Arrieta looked well on his way to being an ace — and then wasn’t even called upon to start Games 1 or 2 of the NLDS for the Cubs. He has dominated for parts of the past three seasons — including all of 2015 — but he has still eclipsed the 200-inning plateau only once, and his second half in 2016 raises concerns. His strikeout rate declined to 7.5 per nine innings from 9.5 per nine. His FIP jumped to 4.19 from 3.03. Basic heat maps indicate that Arrieta’s swing-and-miss abilities with his slider declined in the second half. Arrieta has an extreme cross-body delivery that creates great deception when he is mechanically sound, but causes real trouble when those mechanics are off even a little. He possesses the strength and athleticism required to harness such a delivery, but there’s a question of sustainability, and until he answers those questions by delivering consecutive dominant seasons, he’ll remain just outside of the ace tier.

The Mets’ young arms aren’t the only ones dogged by health concerns: Elbow ligaments and shoulder muscles tear long before amateur pitchers leave college, or even high school, largely because of overuse and poor mechanics. The high-visibility youth showcase in Jupiter, Florida, in late October — when most professional pitchers have shut themselves down — is heavily attended by scouts and keeps teenagers throwing to the radar gun when they could be resting their arms. What’s happening to these kids is directly impacting the major league product. Some major league trainers believe that we’re a generation away from correcting the problem and giving rise to a less injury-prone group of ballplayers. The kids playing Little League now who have yet to fall prey to year-round baseball showcases represent the beacons of hope. If they rest their arms, play multiple sports instead of focusing solely on baseball, and ignore the radar guns, and if Major League organizations cease to place such a scouting emphasis on every showcase, then and only then do elbow ligaments have a chance. The game is not replenishing its aces, and it’s still struggling to protect some of them despite best intentions.

It’s not just about training and development, of course; it’s about how pitchers cope with injury once they’re in the pros. Was Harvey in the express lane to becoming an ace because he ignored post–Tommy John innings limits and took the ball deep into October in 2015? Was Strasburg a mere mortal because he sat idly while the ball was taken out of his hand during the Nationals’ 2012 postseason? The endless coverage of both situations seemed to thrust ace status upon two men who had yet to achieve it, and both had to endure the media’s double-edged sword. The Nationals’ handling of Strasburg appeared prescient until a partially torn pronator tendon in his pitching arm ended his season in early September, and Harvey’s mounting arm injuries bring to mind the sadly curtailed career of Mark Prior. Ace-quality stuff doesn’t necessarily guarantee ace standing.

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Verlander’s best years are behind him after logging nearly 1,000 ace-caliber innings over a four-year period beginning in 2009, when his average fastball velocity was better than 95 mph. Yet pitching at 33 years old in 2016, he enjoyed a resurgence with an average fastball velocity of 93.7 mph and a WAR of 5.2, his best marks since 2013 and 2012, respectively. A strand rate of nearly 80 percent suggests it will be difficult to repeat that success, memorialized by his second-place finish in the AL Cy Young voting. But with restored good health allowing once again for sound mechanics and a current contract guaranteed through 2019, he has many innings left in which to try. A true ace will adapt and redefine himself on the downward arc of his career; Verlander’s proving that by posting a strikeout rate that matches his prime years and logging the kind of quality innings that reduce the pressure on his teammates and manager.

Vanishing Aces

Between the lines, the collective all-or-nothing offensive approach is paying off; while homers and K’s are both occurring at all-time rates, runs per game in 2016 were also the highest since 2009. Highly specialized bullpens have altered expectations. Many teams are happy to have six quality innings from a starter before turning the game over to the relievers.

Injury is suppressing the ace. The Tommy John culture threatens the emergence and mere existence of the ace. Longevity is quickly becoming as antiquated as black-and-white footage of games at the Polo Grounds. Someone has to throw these innings. They can’t all migrate to the bullpen, regardless of what a pitcher’s numbers the third time through the lineup, this offseason’s signings and trades, and October strategy may suggest.

A six-month season cannot be managed like a best-of-seven series. Further specialization out of the bullpen, or even redefined relief roles and demands, only temporarily masks the deterioration of elite starting pitching. Balancing a club’s desire to protect pitchers with the need to develop them creates a tension between two often-opposing forces, but the future of elite starting pitching depends upon establishing an equilibrium.