In 2021, eight MLB teams posted run differentials of +100 of better. Six of those won their divisions; a seventh won 105 games and the second best record in baseball, simply having the misfortune of being in the wrong division in the wrong year.
The eighth team was the Toronto Blue Jays.
Despite posting the fifth best run differential in baseball at +183, they finish fourth in their division, sixth in the American League, and ultimately on the outside looking in of the MLB postseason.
A quick aside before proceeding: I realize some dismiss run differential as a true underlying measure of the quality or greatness of a team, since it’s about winning actual games and not piling up runs in blowouts against basement dwellers. While true, the relationship between runs and wins is very strong, with under- and over-performance having little predictive power in terms of underlying factors or following trend from season to season.
Consider that in the last 50 full seasons since the major expansion of 1969 (excluding 1981, 1994 and 2020), 243 teams have posted run differentials of +100 or better. They averaged more than 96 wins, with an absolute minimum of 84. Just 18, or 7%, won less than 90 games. Focusing on the even more exclusive group of the 106 teams with 150+ run differentials, the average is 99.5 wins. Exactly one (2014 Athletics) failed to win 90 games, and just 16 finished short of 95 wins. Teams that massively outscore their opponents invariably win a lot of games.
Even if that’s not sufficiently convincing, the bottom line is that at core, baseball is a game of run scoring and run prevention. If nothing else, those teams with great run differentials who underperform in terms of wins are among the best at doing the things that over time to winning more baseball games. They are great teams in at least that sense.
The Jays are certainly not the first very good team to suffer the indignity of not playing beyond the final day of the regular season, particularly in the AL. Just in 2019, Cleveland won 93 games with a +112 run differential, but behind Oakland and Tampa Bay at 97 and 96 wins respectively. In 2012, Tampa missed the wild game with 90 wins and a +120 run differential (behind the +7 Orioles and the 88 win Tigers in the AL Central).
These were very good teams, but even they fell significantly short of the run differential dominance of the 2021 Jays, who were in an even more select club of teams who have posted run differentials of 150+. In the decade since the current playoff format began in 2012, 29 teams have done that. 23 of them won their divisions, with five of the remaining six securing spots in the wild card. The Jays are the first to fail to do so.
From a historical perspective, it’s really even worse than even that. The pre-2012 Wild Card era also saw its fair share of very good or great teams miss the playoffs. The infamous 2011 Red Sox for example missed the playoffs with 90 wins and a +138 run differential (fourth best across MLB).
A spate of teams in the early-2000s provide the closest precedent to what happened to the 2021 Blue Jays. In 2005, Cleveland won 93 games with a correspondingly robust +148 differential, with Oakland at 88 wins and +114 behind them. In 2003, Seattle also missed out with 93 wins and an even better +158 differential (in the NL, Houston was the first out with a ore modest 87 wins but +128 differential).
But the prime example would be 2002, when both Boston and Seattle each won 93 games, with run differentials of +194 and +115 respectively, but were playoff also-ransas Anaheim won 99 games for the wild card while Oakland and the Yankees took the divisions with 103 wins. One other notable example to point out is the 1999 Cincinnati Reds, who won 96 games with a +154 differential (one game behind both the wild card and division).
So teams have missed the MLB postseason in its modern incarnation with excellent run differentials, and the 2002 Red Sox are even an example with an even superior differential. But all those teams finished 5th in their leagues (or better, ahead of other division winners). Granted, the incentive structure would be different so we can’t map the standings 1-to-1, but all else equal in the current system they’d have made the wild card game (or in 2002, first a tiebreaker to advance to that game).
In the 26 full seasons of the Wild Era, 66 teams have posted 150+ run differentials. Over three-quarters won their division, so not getting a guaranteed series is already a below average outcome. Another 13 were a wild card, with another two finishing 5th. Only the 2021 Toronto Blue Jays finished 6th.
Going back even further than that makes the basis of comparison less relevant since only division winners made the playoffs. The 1969 expansion to 24 teams and realignment to four divisions created the LCS era, and there’s no precedent in those 24 full seasons either:
34 of 40 teams that posted a 150+ run differential won their divisions, an even higher proportion than the current era, though that also meant 15% missed out. Still, all of those finished among the top four in the league and would have been a wild card had the concept existed. No fifth place team, much less sixth place team, ever posted a 150+ differential in this time.
There’s no sense going back further, since 5th or 6th place didn’t have the same meaning in much smaller leagues where that was the bottom half rather than closer to contention.
Thus, in my estimation, the 2021 Blue Jays have a claim as the best 6th place team in MLB history, contested perhaps only 2002 Red Sox/Mariners.
Looking back, 2021 is far from the first time the franchise has been similarly snakebitten in terms of run differential juggernauts being left out of the postseason.
In 2008, the Blue Jays also significantly underperformed their run differential significantly, finishing with just 86 wins despite a +104 differential that ranked 6th in MLB. Then too, that was only good for 4th in the division, but also 7th in the American League writ large.
Not only is that only one of 10 teams since 1969 to post a 100+ run differential without finishing top-5, they’re the only one not to finish 6th. So in addition to the best 6th place team in MLB history, they also probably have the best 7th place team in MLB history (the 1977 Minnesota Twins appear to be the next closest with 84 wins and a +91 differential).
1987 was the year of the Blue Jays’ own infamous collapse, losing their last seven games all by three runs or less to lose the division on the last weekend of the season. If that wasn’t painful enough, adding insult to injury was that their 96 wins would have been enough to win any of the other divisions; they missed the playoffs with the second best record in baseball.
From a run differential perspective, it’s even more historically ignominious. Their +190 differential was the best in baseball, well ahead of Detroit’s +161 (and the third place Mets at +125). In the post-expansion era, no team failed to win their division with that good a differential, the next closest being the 1993 San Francisco Giants with 103 wins and a +172 differential.
One final note: while throughout I have used 150+ differential teams as the basis for comparison for the 2021 Jays, I have also included the data for 100+ win teams. I believe 150+ is the best comparison, but in recent years 150+ has become less rare. 2021 was the first year with six of those teams, after five in each of 2017-19 when that mark that never been reached prior. Before that, there had only been four 150+ differential teams in the same season four times.
This may be a short term blip, or a result of modern management where there’s a bunch of teams in hardcore build/tank mode. To the extent it’s the latter and little is done to address the incentives, then 150+ will become more common and less meaningful than before, more on par with 100+ in the past in terms of frequency.