If modern baseball analytics had Ten Commandments, carved into stone tablets brought down from atop the Green Monster, one of them would undoubtedly be “Never trust a pitcher.” The unpredictability of pitching, and the massive attrition the profession brings, is an inherent part of the game. More than almost any other position in sports, a pitcher’s success depends on the health of a single limb, and even a slight tweak in the kinetic chain from the shoulder to the fingertips can devastate a career.

Pitchers can’t be trusted at any point in their careers. Pitching prospects bust far more often than hitting prospects. Pitching phenoms in their early twenties frequently burn out before they reach their thirties, which is extremely rare for hitting phenoms. Even the best pitchers can see their careers end overnight, at the height of their powers. Ask Brandon Webb. Or Roy Halladay.

“You can never have too much pitching” is one of the principal edicts of traditional baseball thinking. Like Fabergé eggs, elite pitchers are both priceless and exceedingly fragile, and the tension between those two truths is one of the greatest challenges facing the architects of Major League Baseball’s 30 teams. A general manager will do anything to get his hands on a no. 1 starter, knowing full well that, even once acquired, the ace might slip through his grasp like water.

This is why teams are rarely willing to make the same commitment to ace starters as they are to elite hitters, even though they covet the arms as much as or more than the bats. Teams will commit 10 years to elite hitters like Albert Pujols and Troy Tulowitzki and, yes, Alex Rodriguez. Joey Votto is at the beginning of a 12-year commitment.

In contrast, only two pitchers have ever received a guaranteed contract of eight years or more, and both deals wound up being as disastrous as you’d think. Following the 1976 season, at the dawn of free agency, the Cleveland Indians gave a 10-year contract to a 26-year-old pitcher who’d just won 20 games with the Baltimore Orioles, back when winning 20 games was next to godliness.

That pitcher was Wayne Garland. In his first year with the Indians, he led the league in losses. The next year, he tore his rotator cuff. His career ended halfway through his contract, after he’d gone 28-48 with a 4.50 ERA in Cleveland and given the Indians just 3.3 bWAR.

Nearly a quarter-century later, during the funny-money free-agent bubble of 2000-01, a team rolled the dice again. The Colorado Rockies, desperate for pitchers who could solve the riddle of Coors Field, gave Mike Hampton an eight-year contract. Hampton had finished second in Cy Young voting while pitching for the Astros in 1999, then had pitched the Mets to the World Series in 2000 with two scoreless starts against the Cardinals in the NLCS. The Rockies figured the extreme ground ball pitcher held the antidote to Coors Field’s thin air.

Hampton lasted all of two years in Colorado, posting a 5.75 ERA. He was traded to the Marlins in a salary dump after the 2002 season, and then traded to the Braves in another salary dump two days later. With three-quarters still to go, Hampton’s deal was so toxic that it was split up among three investors like a collateral debt obligation.

Never trust a pitcher. Teams that ignore this maxim do so at their own peril.

And yet every rule carries a defining exception. “I before E” has “except after C.” “Freedom of speech” has “shouting ‘Fire!’ in a crowded theater.”

“Never trust a pitcher” has Clayton Kershaw.

♦♦♦

Last week, the Dodgers signed Kershaw to a seven-year, $215 million extension, making the 25-year-old lefty the highest-paid pitcher in baseball history. Of all the remarkable things about Kershaw’s career to this point, perhaps the most remarkable is how unremarkable it has been. There have been no crisis points, no unexpected breakthroughs or setbacks, no injuries. Even the most talented pitchers tend to oscillate up and down like penny stocks, but Kershaw has risen as steadily and inexorably as a long-term bond generating amazing, almost Madoff-ian returns. There’s been no drama, only excellence.

Kershaw’s excellence was hard to miss even in high school, and he was nearly universally considered the best high school arm in the 2006 draft. He fell to seventh in that draft because the Rays picked Evan Longoria — no complaints there — and the other five teams picking ahead of the Dodgers elected to take college pitchers, presumably figuring the college arms would reach the majors first.

In his first pro season, Kershaw threw 37 innings in rookie ball, striking out 54 and walking five. The next year, at 19, he tore through the low-A Midwest League, striking out 134 batters in 97⅓ innings, prompting the Dodgers to send him all the way to Double-A late in the year, where he struck out 29 batters in 24⅔ innings. He was all power at that point, wielding a mid-90s fastball and a curveball that even then elicited whispered comparisons to Sandy Koufax; Kershaw’s command evoked comparisons to a young Koufax as well, as he walked 67 batters in just 122 innings that year. Despite the walks, Kershaw ranked as Baseball America’s seventh-best prospect and Baseball Prospectus’s fifth. He checked in behind two pitchers on each list: Clay Buchholz and … Joba Chamberlain. Oops.

That was pretty much the last time Kershaw ranked behind any other pitcher in his peer group. He introduced himself to the wider baseball world in a game the following spring training, by displaying a curveball that Vin Scully immediately pronounced “public enemy no. 1.” Kershaw was still days shy of his 20th birthday; three months later, in May 2008, he was in the majors for good. He was still raw while pitching for the Dodgers that year, his command was still poor (52 walks in 107⅔ innings), and his BABIP was .323 (suggesting some bad luck on balls in play), but he still managed a 4.26 ERA; he was basically a league-average starter.

Kershaw still had command issues in 2009, but he was practically unhittable, leading the majors by allowing just a .200 batting average to opposing hitters. It helped that the Dodgers taught him to throw a slider at midseason, and he mastered it so effortlessly that it almost immediately became his best pitch. Kershaw’s fastball/curveball combination got him to the majors as essentially a two-pitch pitcher at age 20, and by 21 he’d developed a third pitch better than the other two.

Kershaw has steadily climbed to ever more dizzying heights from there. He finished 2009 with a 2.79 ERA in 171 innings; in 2010 his ERA rose to 2.91, but he crossed 200 innings for the first time. His ERAs checked in at 2.28, 2.53, and 1.83 over the next three years. Kershaw has improved not by becoming more dominant — after striking out 21.3 percent of batters as a rookie, his strikeout rate has hovered between 25.0 percent and 27.2 percent every year since — but by becoming more polished. Here are his walk rates for every year of his career, listed chronologically: 11.1 percent, 13.0, 9.6, 5.9, 7.0, 5.7.

And here is his overall annual value, as measured by bWAR: 1.4, 4.7, 5.5, 6.5, 6.2, 7.8.

If fancy stats aren’t your thing, consider this: In each of the last three years, Kershaw has led the majors in ERA and led the NL in WHIP. In 2011 and 2013, he led the NL in strikeouts and won the NL Cy Young; he finished second in both of those categories in 2012.

♦♦♦

Kershaw’s excellence is rare, but not unprecedented. He actually trails Justin Verlander slightly in overall value over the last three years, with a 20.6 bWAR to Verlander’s 20.8. Kershaw has posted three consecutive six-plus WAR seasons; Halladay posted four straight from 2008 to 2011.

What separates Kershaw is his age. He started his remarkable three-year run when he was 23 years old. He doesn’t turn 26 for another two months. His age, as much as his performance, prompted the Dodgers to award him the highest average annual salary in major league history. As historic of a commitment as that is, the Dodgers are only wedded to Kershaw through his age 32 season.

Few pitchers in baseball history have accomplished as much as Kershaw at such a young age. Here’s a list of the pitchers who have accumulated the most value through their age 25 seasons, since 1901:

Rank Player bWAR 1 Walter Johnson 59.6 2 Bert Blyleven 44.0 3 Christy Mathewson 40.2 4 Bob Feller 37.3 5 Hal Newhouser 37.1 6 Don Drysdale 34.2 7 Dwight Gooden 33.2 8 Frank Tanana 32.5 9 Bret Saberhagen 32.3 10 Clayton Kershaw 32.2

It’s true that great young pitchers burn out at an alarmingly high rate. It’s also true that the first six names on this list are enshrined in the Hall of Fame. These aren’t simply great young pitchers; these are the greatest young pitchers since 1901, and since we’re measuring them through their age 25 seasons, we’ve already weeded out those pitchers who blew their arms out in their early twenties, like Gary Nolan, Don Gullett, Herb Score, Mark Fidrych, and Mark Prior. The list goes on and on.

The three pitchers on the above list who didn’t wind up in the Hall of Fame all showed signs of breaking down by the time they’d reached the age Kershaw is now. Dwight Gooden is the greatest teenage pitcher of the last 75 years; only Bob Feller was more successful in the majors at such a young age. When Gooden was 20 years old, he delivered a 1.53 ERA over 276⅔ innings, the second-lowest ERA of the live ball era. Gooden was worth an astonishing 12.1 bWAR that year, the highest single-season total by any pitcher in the last 100 years. But Gooden was never again as dominant as he was in his first two seasons, and in 1989, at the tender age of 24, he tore his rotator cuff and missed half a season. While he made a full recovery the following year, he was never again the same pitcher. Gooden was worth 3.5 bWAR or more in each of his first five seasons in the majors, but was never worth more than 3.5 bWAR again.

The same year that Gooden put together one of the greatest pitching seasons of all time in the NL, Bret Saberhagen won the Cy Young in the AL, culminating with a shutout start in Game 7 of the World Series. But the following year Saberhagen nursed a tender arm, missed a month of the season, and saw his ERA rise to 4.15. Thus began his notorious even-year/odd-year pattern, in which he delivered great seasons in odd-numbered years but mediocre seasons in even-numbered years, because he was unable to sustain full health in back-to-back campaigns. He had his best season in 1989 at age 25, winning his second Cy Young Award, but managed only one more fully healthy season in his career, although he was usually still effective when he could take the mound.

Frank Tanana was the Kershaw of his day, a left-handed fireballer with a great curveball who was in the majors when he was barely 20 and led the majors in strikeouts in his second full season and ERA in his fourth. But after missing the last month of the 1977 season with a triceps injury, his strikeout rate tumbled, and in 1979, just shy of his 26th birthday, Tanana suffered a rotator cuff injury that turned him into a full-on junkballer. He still lasted 21 years in the majors, winning 240 games and finishing with 57.5 bWAR.

So of the nine pitchers with more success than Kershaw at this age, six are in the Hall of Fame, and three had exhibited warning signs by age 25 that something wasn’t right with their arms. And two of those three had productive careers after their 26th birthdays anyway.

And this isn’t simply a case of cutting off the list after 10 names in order to make the results look good. Of the five pitchers who rank from 11 to 15, two (Robin Roberts and Dennis Eckersley) are in the Hall of Fame, one (Wes Ferrell) is widely considered to be one of the best pitchers not in the Hall, and one is Roger Clemens.

Pitchers get hurt a lot, and even when they don’t get hurt, they often inexplicably lose velocity. But pitchers who are this good this young have too much ability to see their careers threatened by anything less than a major arm injury. Which isn’t to say that can’t happen at some point during Kershaw’s contract; seven years is a long time. Don Drysdale is in the Hall of Fame, but his last good season came at age 31 and his career was over a year later. Hal Newhouser was through as a full-time starter by age 30. Even though Kershaw has yet to show any hint of arm trouble, history tells us there’s a chance the back end of this contract could be dead money.

♦♦♦

That risk, however, is largely mitigated by the one advantage Kershaw has over every other pitcher we’ve mentioned so far: He’s the first pitching phenom of this caliber to come of age in the Pitch Count Era, which began roughly in 1998. Through his age 25 season, Kershaw has thrown only 1,180 innings, 149 fewer than every pitcher ahead of him on the above list. That’s impressive in its own right, because it means Kershaw was able to provide comparable value to his team despite throwing fewer innings. On an inning-for-inning basis, Kershaw would rank third among the pitchers in the top 15, behind only Clemens and Walter Johnson.

It also means Kershaw’s arm has more bullets left in it than the great pitchers of yesteryear had left in theirs. There’s probably a direct connection between the 276⅔ innings Gooden threw at age 20 and the rotator cuff tear he suffered at age 24. Newhouser averaged 295 innings per year from age 23 to age 28, and was a shell of his former self by age 30. Drysdale threw more than 300 innings in four consecutive years from age 25 to age 28. Tanana’s triceps injury in 1977 occurred after he had completed 14 games in a row.

These guys were worked hard, and eventually that took its toll on their bodies. Johnson won an MVP award at age 36, but most of these guys — even an all-time great like Christy Mathewson — saw their effectiveness wane by their early thirties.

Things are different now, and the changing patterns in pitching usage, as much as Kershaw’s undeniable talent, should make the Dodgers comfortable in his ability to stay healthy in the coming years.

The change in the way pitchers are used is best demonstrated not simply by innings totals, but also by pitch counts. We don’t have pitch count data for most of major league history; these totals were only tracked in earnest beginning in 1988. The last great young pitcher for whom we have data is Saberhagen, who was even better in his age 25 season (9.7 bWAR) than Kershaw was last year.

Based on innings pitched alone, the difference between their age 25 seasons isn’t so great: Saberhagen threw 262⅓ innings, Kershaw 236. But in Saberhagen’s 35 starts that year, he threw 120 or more pitches 12 times, and 130 or more pitches three times. Kershaw reached 120 pitches just twice all year. Kershaw has exceeded 120 pitches just three times in his entire career.

Even Saberhagen’s pitch counts pale in comparison to pitchers from earlier generations. While pitch counts before 1988 are almost nonexistent, there is one exception: Allan Roth, who was hired by Branch Rickey to be the first full-time statistician, kept pitch-by-pitch data for the Dodgers from late 1947 until late 1964. That happens to overlap with much of Drysdale’s career, giving us a window into a very different game.

We have pitch count data for 293 of Drysdale’s 465 career starts. In those 293 starts, Drysdale:

• Threw 120 or more pitches 77 times

• Threw 130 or more pitches 39 times

• Threw 140 or more pitches 17 times

• Threw 150 or more pitches nine times

• Threw 160 or more pitches six times, including outings of 173, 175, and 182 pitches

In 1962 alone, Drysdale’s age 25 season, he exceeded 130 pitches seven times. Every pitcher in the majors in 2013 combined to exceed 130 pitches twice.

So while Kershaw is not the best young pitcher of all time, he is the best young pitcher of the Pitch Count Era. And while it’s too soon to know with certainty if limiting pitch counts will reduce pitcher injuries, the early signs are positive, as we documented with Stephen Strasburg in 2012.

Sum it up thus: In baseball history, no pitcher who has been protected as much as Kershaw has pitched as well at such a young age.

Injuries still happen, whether from overuse, trauma, or just bad luck. It’s entirely possible the Dodgers will wind up eating most of the $215 million they just promised Kershaw. Webb, after all, earned more than half of his career income after he’d already thrown his last pitch in the majors. But every contract involves risk, and it’s quite possible that no pitcher has ever represented less risk over the ensuing seven years than the soon-to-be 26-year-old Kershaw.

♦♦♦

Are there other risks associated with this contract? Well, Kershaw spends his offseasons building orphanages in Africa, so no one’s going to confuse him with Jordan Belfort. There’s also no reason to think Kershaw’s $30 million average salary will hamper the Dodgers’ ability to spend on other players. The Dodgers have become the biggest spenders in baseball history. They’ll pay Matt Kemp, Carl Crawford, and Andre Ethier a total of $57 million in 2014, and one of those three will have to sit to accommodate Yasiel Puig. Another $30 million is ashtray money for these guys. The Dodgers, and increasingly the rest of baseball, care less about the money they’re spending than the talent they’re playing. In Kershaw, they have the most talented pitcher in the world, entering what should be the prime years of his career.

Truthfully, the biggest risk with Kershaw’s new contract is that it might not last for seven years at all. While awarding eight-year contracts to pitchers is a line teams dare not cross, seven-year deals aren’t unheard of. Just in the last year, Verlander and Felix Hernandez received seven-year commitments from their teams.

But Kershaw didn’t actually sign a seven-year deal. Thanks to an opt-out provision in the contract that allows him to walk away after the 2018 season, Kershaw’s deal is better described as a five-year, $150 million extension, with a player option to stay for an additional two years and $65 million. The risk that the Dodgers won’t want to pay Kershaw $65 million for his age 31 and 32 seasons is equaled by the risk that they will want to pay him, but won’t be able to, because he’ll be entitled to enter free agency at the still-young age of 30. If Kershaw pitches as well over the next five years as he has over the last five years, his next contract may well dwarf this one.

But for now, the Dodgers are assured of getting Kershaw’s age 26 through age 30 seasons, which just so happens to coincide with the peak of the greatest Dodgers left-hander of them all, and the name that has shadowed Kershaw for his entire career: Koufax.

Koufax finally harnessed his command in 1961, at age 25. In 1962, the Dodgers moved into pitcher-friendly Dodger Stadium, and Koufax commenced the greatest five-year stretch by a 26-to-30-year-old pitcher in the live ball era. Koufax led the NL in ERA five straight years and the majors in WHIP four straight times. He also led the majors in strikeouts three times during that span and set the then-modern major league record for strikeouts with 382 K’s in 1965. He won three Cy Youngs and finished first or second in the MVP vote three times. He was, for five years, the platonic ideal of what a pitcher should be.

And then he was gone. Ravaged by an arthritic left elbow, Koufax walked away from the game at the age of 30.

Incredibly, Kershaw has so far been a better pitcher than Koufax was at the same age in every season of his career. But then, Koufax wasn’t Koufax until he turned 26. It’s no insult to Kershaw to say that he’s unlikely to match Koufax’s performance over the next five years; unless the Dodgers plan to let Kershaw throw 300 innings a year, it’s almost impossible. But Kershaw will likely be pretty damn good. And thanks to modern medicine (Koufax retired eight years before Frank Jobe operated on Tommy John) and modern pitcher handling (Koufax once threw 205 (!) pitches in a start), Kershaw will likely still be one of the best pitchers in the game at an age when Koufax had long since retired.

Every rule has an exception. For almost any other pitcher, a seven-year contract would be far too long a commitment to make. For Clayton Kershaw, the Dodgers’ biggest regret might be that their commitment wasn’t long enough.