By: Tate Huffman
We are just past the midway point of the 2018 MLB season, and with every team having played over half of their 162-game schedules, the standings are a mix of preseason favorites and surprise squads. The common consensus is that the league’s three best teams, both in the standings and on the statistics leaderboards, are the Astros, Red Sox, and Yankees. All three were 2017 playoff participants who made significant improvements over the offseason; the Astros by trading for Pirates ace Gerrit Cole and the Red Sox and Yankees by acquiring J.D. Martinez and Giancarlo Stanton, respectively.
However, while all three teams are locked in heated races for their all-important division titles, the situations are wildly different. The Red Sox and Yankees are significantly ahead of their AL East rivals and are only engaged in a battle with each other to avoid the one-game wild card playoff. The two are the majors’ top teams in runs per game, home runs, and OPS while also boasting pitching staffs that have held opponents to less than four runs per game.
Meanwhile, as dominant as the Astros seem on paper, they seem unable to pull away from the Mariners in the AL West, holding a mere three-game lead, an advantage that recently has been as small as half a game. While the Astros were penciled in as the division champs almost as soon as the last out was recorded in last year’s World Series, their division race has remained competitive into July – against a team that holds the league’s longest playoff drought, to boot.
The explanation for this surprisingly close race lies primarily in the two teams’ difference in luck so far this season. Even though the Astros seem like far and away the best team in baseball, given how they lead the majors not only in many offensive stats, including wRC+ and OPS+, but also nearly all pitching measures as well (with a stellar team FIP of 3.10, well ahead of the 2nd-place Red Sox’s 3.55), they have a slightly below-average record of 13-16 in one-run games that ranks 20th in the MLB. Standing in sharp contrast in this regard, the Mariners are an astounding 26-11 in their one-run contests, which would be the fourth-highest mark in the wild card era, and are also the last team this year to remain unbeaten in extra innings.
Records in both one-run and extra inning games tend not reflect a team’s underlying ability level and are more due to chance, although bullpen strength can have a decent effect on their outcomes. While the Astros have slightly underperformed the norm in these situations, it’s not markedly out of the ordinary. Their bullpen holds the majors’ lowest FIP and second-highest K/9, but their offense hasn’t performed as well in this small sample size, ranking as one of the bottom teams in the league in runs scored in extra innings, a trend that will likely correct itself as the season progresses.
The Mariners, on the other hand, have been much more fortunate than the Astros. While their bullpen is among the top in baseball, it’s a step behind the Astros and Yankees, ranking in a solid upper tier with the Rangers and Diamondbacks. Their advantage in these scenarios, while primarily due to good fortune, also comes largely from closer Edwin Diaz, who has the highest fWAR and third-lowest FIP (minimum of 30 IP) of all relievers – and eight more saves than anyone else. While the Mariners’ abnormal performance in these close late-game situations makes their success so far seem less sustainable in the second half, their six-game lead on the Athletics for the second wild card spot makes it more likely than not that they will snap their playoff-less streak (though the A’s recent 17-4 hot streak is worth noting). Fangraphs projects them to have the 4th best record in Major League Baseball at the end of the season.
While both teams are favorites to make the playoffs, the fact that they are engaged in such a close race remains befuddling, particularly when viewed through the lens of run differential. The Astros’ RD of +181, by far the best in the majors – and the best at this point in the season of any team in the wild card era – would predict a Pythagorean win-loss record (based on runs scored and runs allowed) of 66-27, on pace for a 115-win season. Meanwhile, the Mariners’ RD of +17, which is actually behind the +19 of the A’s and just ahead of the Angels’ +14, a team they lead by eleven games in the AL West, would put them at 47-44, ten games worse than their current record of 57-34.
Essentially, the Astros should be having an all-time great season, while the Mariners should be struggling to stay above .500. Yet here they are in July, much closer than anyone would have anticipated. So what’s the precedent for this situation? In fact, there isn’t really one. In the wild card era (including the strike-shortened 1994 season, which was the first to feature the current three-division format), there has only been one division race with a larger gap in run differential between the first and second-place teams in a division through this point in the season:
Difference in RD >= 100 between 1st and 2nd through 7/09 in Wild Card Era
** start of season was delayed by continuation of 1994 players’ strike
The most striking part of this is how even though this year’s “difference in differential” has only been bested by one race since the wild card began in 1994, there has also only been one race closer than it – last year’s AL Central, which featured a Cleveland Indians team that won 102 games and still underperformed their Pythagorean expectation by six wins and a Minnesota Twins squad that had the lowest win total of any playoff team since 2008.
It also should be acknowledged that the one race with a greater RD differential between first and second involved last year’s Astros team, and apart from reinforcing how much better they’ve been than the rest of their division recently, this also makes clear how much of an anomaly this year’s race is. Last year, the difference in differential between first and second (referring to both the Angels and Rangers) was similar to this year’s, but the gap was reflected in the standings, as the Astros had a cushion of 16.5 games, as opposed to the three-game lead they currently hold. Essentially, by using difference in RD as a proxy for difference in team talent, this *should* be one of the most – if not the most – lopsided division races we’ve seen in recent years, but given a certain disparity between first and second, it’s actually been one of the closest.
Astros fans, however, can feel comfortable that each of the teams leading at this point in the above table went on to win their divisions, in nearly all cases by double digits – only two races finished with a margin of five games or less, the 2012 AL East and the 2005 NL West. The 2012 AL East, which ended with the Orioles narrowly losing out on the division title to the Yankees, was largely a result of Baltimore’s absurd 29-9 record in one-run games, behind only the 2016 Rangers for tops all-time (and while this may draw comparisons to this year’s AL West race, the Mariners haven’t been as lucky as that Orioles team, and this year’s Astros team is miles better than that Yankees side – in fact, their run differential of +186 is the best of any team through this date since the wild card was introduced). Meanwhile, I’m trying to discuss the 2005 NL West as little as possible, so I’ll just say that the Padres won the division at 82-80 – the large RD differential came not because they were good, but because the rest of the division was absolutely atrocious.
In a final interesting fact, each of the last two years has featured a team with a massive advantage in run differential over its closest division competitor, and in both years that team has gone on to win the World Series. And while we haven’t seen a team repeat as champs since the Yankees’ 1998-2000 three-peat, the Astros look to be in a pretty good position to do so – with this unusual division race the first step to overcome.
All statistics through 7/09/18
Thanks to Fangraphs and Baseball-Reference for the above data
If you have any questions or comments for Tate, please feel free to reach out to him by email at firstname.lastname@example.org