The weather is getting colder, and for some reason, so are the Tigers' bats. The same team that posted a reasonably healthy five-runs-per-game average in August only managed to accumulate an average 3.7 runs-per-game in September, and two of those games were outliers in which the Tigers scored a combined total of 28 runs. Take those games out of the equation, and the Tigers posted an anemic 2.9 runs-per-game average in September, which goes a long way towards explaining why they finished the month with a .500 win percentage.
Losing one to two full runs per game in the span of a month seems pretty dramatic. The most obvious answer to the riddle is Miguel Cabrera, who has seen a significant decline in his batting numbers from August to September, the most significant being a 400 point drop in his slugging percentage. But as the Village People once said (probably), "It takes a village, people." Cabrera may be a major piece of the puzzle that is the Tigers' slumping offense, but he's certainly not the only reason. The Tigers played 13 games this year from July 4 through September 22 without Miguel Cabrera in the lineup, and posted a record of 9-4 with an average of five runs-per-game. Five of those games were blowouts in which the offense scored six or more runs. Clearly, they know how to bring the hurt even without Cabrera in the lineup.
September has been a cold month for several of the regular starters. Of the "murderer's row" consisting of Torii Hunter, Miguel Cabrera, Prince Fielder and Victor Martinez -- the players responsible for more than half of the team's total RBIs this season -- only Fielder has seen an upward trend in his hitting statistics from August to September. Hunter's slugging percentage has dropped 50 points. Austin Jackson's on-base percentage has dropped 48 points. Victor Martinez's OPS has dropped 90 points, with the main culprit being an 82-point drop in his on-base percentage. Hunter appears to be struggling the most with plate discipline, as his strikeout rate doubled from 13% in August to 26% in September.
The other bats are similarly struggling. Andy Dirks, who looked like he might be heating up in August with a slashline of .286/.408/.413, has seen a 97-point drop in his on-base percentage, and a 148-point drop in his OPS. Omar Infante dropped 53 points in his OPS. Austin Jackson, who the Tigers look to for those early initial runs as the leadoff man, has suffered a 119-point drop in his OPS. That's a significant loss, considering that in the 65 games this season where Jackson has scored at least one run, the Tigers' win percentage is .738, but it drops to .453 when he fails to score. As for the flashy defender at shortstop, Jose Iglesias dropped 117 points in his on-base percentage from August to September, for an overall OPS drop of 162 points.
There is bound to be major impact when the team's MVP drops 435 OPS points in a month, but the numbers show that the majority of the offense has followed suit and gone into an autumn slump. It's difficult to pinpoint a logical reason. Cabrera's injury didn't cause Hunter's strikeout rate to double, or Iglesias to regress, or Jackson to lose 119 OPS points in a month. It might be conventional baseball wisdom to say that "hitting is infectious," but it's doubtful that any one of these hitters would agree that they approach the plate differently based on whether or not Cabrera is launching home run bombs.
There may be good news hidden in all of this. Prince Fielder is still hitting. His strikeout rate went down 3% from August to September, and his slashline went from .289/.358/.455 to .337/.396/.537, good for an OPS increase of 120 points. Alex Avila, who missed a lot of August due to injury, posted a September slashline of .343/.430/.522, for a solid OPS of 953. Injuries take time to heal, and Cabrera probably won't be back to form until next year, but years of evidence indicate that slumps come and go almost arbitrarily, vanishing just as quickly as they appeared. If the majority of the offense is slumping, and for no particularly logical reason, there may be hope that the slump will soon be replaced by the team that was able to score an average five runs-per-game in Cabrera's absence this year. Hopefully it will be sooner than later, because we're into the postseason now. There may not be the luxury of weeks to go in which to get things sorted out.