As of Monday afternoon, the Rangers and Cardinals have baseball’s best records. Not entirely coincidentally they also have the best run differentials of any team in baseball. The Rangers have scored 212 runs and let in 158, putting them at +54. The Cardinals have scored 201 runs and allowed a major league-low 150, which works out to a +51.
It also won’t come as a surprise to anyone which two teams fall at the bottom when it comes to run differential. The Astros and Marlins have identical 12-32 records at the moment, and no other teams are within even 100 points of them when it comes to winning percentage. In run differential, the Astros rate at the bottom, a cool -88. The Marlins aren’t far behind at -73. They’ve gotten respectable pitching (190 runs allowed), but they’ve scored 25 fewer runs than any other team in baseball. The Astros have let in 39 more runs than any other team.
The Astros, in fact, are so bad that they’ve reshaped how we have to look at two divisions since making the switch from the NL Central to the AL West. Last year, the NL Central was the second worst division in baseball by run differential. This year, it’s the best.
NL Central: +86
AL Central: +70
AL East: +49
NL West: +2
AL West: -89
NL East: -118
That’s a huge turnaround from 2012:
AL West: +236
AL East: +123
NL East: +67
NL West: -36
NL Central: -139
AL Central: -251
The Astros alone were a -211 last year. The rest of the NL Central was positive overall, but that’s largely because it got to beat up on the Astros. This time, the division is in the positives without any assistance from the Astros. Well, actually, the Pirates got to play them three times, but that turned out to be a null series; the Pirates won twice by one run and lost once by two runs.
The AL Central has taken an even bigger step forward than the NL Central. The Indians (-178) and Twins (-131) were far and away the AL’s worst teams by run differential last year. This year, the Indians are a +35 and the Twins are merely -11.
The AL East is the only division this year to boast four teams with positive run differentials. However, Toronto’s -45 has wiped out a good portion of that. The Blue Jays have the third worst run differential in baseball.
The NL East has just one team, the Braves, with a positive run diffential at +34. The Nationals are a -17, even though they are 23-21 for the season.
Besides the Nationals, the Giants are the only other team with a positive record (24-20) and a negative run differential (-5). They have the same record as the Rockies, even though the Rockies sit at +32.
There aren’t any teams with positive run differentials and sub-.500 records, though the A’s have been straddling that line. Winning three straight one-run games over the Royals last weekend gave them a 23-22 record and a +3 run differential.
As for the leagues themselves, the AL is currently a +30 over the NL, with a 29-26 interleague record.