If the Boston Red Sox harbored any hopes of returning to the playoffs after last year’s magical World Series run, they knew they’d need to make a very strong push over the regular season’s last couple of months. Boston entered the final week of July running eight games behind in the American League East race, though it had just taken five of six games against the division-rival Tampa Bay Rays and New York Yankees and were scheduled to play 25 of their final 56 contests against AL East opponents. The Red Sox would have plenty of chances, and the FiveThirtyEight model gave them essentially a coin flip’s probability of making the postseason as at least a wild card.

But a weekend massacre at the hands of the Yankees has all but destroyed Boston’s playoff hopes. After New York swept the four-game series (which included a pair of losses in a double-header Saturday), the Red Sox are down to a mere 8 percent chance of getting back to the postseason, with basically no hope of winning the division. As the recriminations begin to fly for Boston’s lifeless title defense, we ask: What has happened to leave a team so good on paper sitting on the outside of the playoffs looking in?

We knew the Red Sox would have trouble replicating some aspects of that charmed 2018 run. After a season in which few things didn’t go according to plan, regression to the mean loomed large. But our preseason predictions still called for Boston to win 95 games, with a 76 percent chance of making the playoffs despite tough division competition in the Yankees and the Rays. Even the most pessimistic of Sox observers wouldn’t have thought Boston’s playoff odds would dip so low by the beginning of August.

What’s interesting is that, by most advanced measures, the defending champs have once again been one of baseball’s best teams in 2019. The Sox still rank eighth in our Elo ratings, seventh in total wins above replacement per game and sixth in the differential between StatCast’s expected wOBA for and against. They have the talent to stand right next to the Yankees, Houston Astros and Los Angeles Dodgers as World Series front-runners.

In fact, on a purely statistical level, these 2019 Red Sox have been far from the most disappointing team in baseball thus far. Last year, Boston’s total team WAR ranked third in MLB, so it has fallen only four slots as compared with its World Series season — only the seventh-biggest drop-off in baseball this year. (In this regard, a better candidate for “most disappointing team” might be the Milwaukee Brewers, whose top players have mostly returned and have mostly played worse in 2019.)

Although Mookie Betts and J.D. Martinez have lost some shine from their dueling MVP campaigns of a year ago, and putative ace Chris Sale is on pace for his worst season by WAR in eight years, other breakouts have attempted to make up the difference. For example, Xander Bogaerts has continued his ascent to become a borderline MVP-level shortstop this year. The 26-year-old is tracking for 6.4 WAR by season’s end, thanks in large part to vastly improved discipline at the plate. Meanwhile, 22-year-old third baseman Rafael Devers has bounced back from a mediocre 2018 season (0.5 WAR) to play at a 5.9-WAR pace (per 162 games) thus far. And catcher Christian Vazquez has also jumped at the chance to be a regular starter behind the plate, producing at a career-high 3-WAR pace this year.

Red Sox pitching has been a hot mess at times. Beyond Sale’s uncharacteristic problems — his ERA-minus of 97 is essentially that of an average pitcher, easily the worst mark of his career — fellow starter Rick Porcello has struggled (115 ERA-minus), 2018 postseason hero Nathan Eovaldi has barely played (26⅔ innings), and the team has gotten practically nothing out of the back end of the rotation. The result has been a staffwide drop from third in pitching WAR (and sixth when looking at starters only) in 2018 to 14th this season (and 15th among starters only).

But these individual efforts explain only a portion of Boston’s 2019 downturn. Collectively, the Red Sox have not played to the sum of their parts, either in terms of their talent or their ability to convert personal statistics into victories. The negative gap between the record we would predict from Boston’s WAR (65-51) and its actual mark (60-56) is tied with that of the Kansas City Royals for the third-largest in baseball. Red Sox hitters have the fifth-worst “clutch” score in the league, according to FanGraphs, and their pitchers are sixth-worst — including dead last among starters. (Clutch measures the difference in a team’s or player’s performance during high-leverage moments.) After a postseason in which Boston pushed all the right buttons during important moments, that ability has deserted them this year.

That was on display over the weekend, when Boston went 3-for-19 with runners in scoring position against the Yankees and mustered zero runs (and only two hits) from the seventh inning onward across all four games. It was also evident in the bigger picture, where the Red Sox’s playoff odds could have gotten a big boost from a strong showing against their rivals. Instead, they were outscored 26-12 in one of the worst “Boston massacres” in the recent history of the game’s most famous rivalry.

Boston’s worst massacres (since 2000) Worst series sweeps suffered by the Boston Red Sox at the hands of the New York Yankees by total scoring margin, 2000-19 Runs Season Month Games Scored Allowed Difference 2006 August 5 26 49 -23 2012 October 3 7 28 -21 2009 August 4 8 25 -17 2019 August 4 12 26 -14 2001 September 3 6 19 -13 Source: Retrosheet

The indignity of losing to the archrival Yankees with the season on the line is bad enough for Boston’s faithful. But the sweep could play a central role in helping make these Red Sox one of the most talented teams to miss the postseason under MLB’s current 10-team playoff structure. According to Elo, Boston’s current 1539 rating would be fourth-highest among teams that failed to play in the playoffs since 2012, trailing only the 2012 and 2018 Rays and the 2013 Texas Rangers. Along the same lines, the Red Sox’s 0.270 WAR per game would tie them for fourth among teams to miss the playoffs since 2012, behind the 2012 Los Angeles Angels, 2012 Rays and 2013 Rangers. Either way you cut it, teams as good as Boston usually play in the postseason.

The Sox would be among the best nonplayoff teams The best MLB teams according to Elo ratings and wins above replacement per game to miss the playoffs, since the 2012 postseason expansion Rk Year Team ELO Rk Year Team WAR/G 1 2012 Rays 1571 1 2012 Angels .277 2 2018 Rays 1543 2 2012 Rays .277 3 2013 Rangers 1540 3 2013 Rangers .272 4 2019 Red Sox 1539 4 2019 Red Sox .270 5 2012 Angels 1536 5 2018 Rays .270 Sources: FanGraphs, Baseball-Reference.com

All is not totally lost for the Red Sox yet, of course. They are too good not to rattle off a streak of wins soon, although they have only split the first two games of their series against the rebuilding Kansas City Royals this week. Elo still considers the Sox roughly equivalent to the Rays and Oakland A’s, the two teams ahead of Boston for the final wild-card spot in the AL. (The Rangers are also tied with the Red Sox in the wild-card standings.) But it will be a tall order to make up a 6½-game deficit and leapfrog two good teams in the final few months of the season. More likely than not, the Red Sox will instead look at 2019 as a missed opportunity, a talented follow-up effort that never quite clicked the same way as the original despite running back mostly the same cast of characters for the sequel.

Check out our latest MLB predictions.