A follow-up look at whether late-season play translates into October success

Yesterday I examined whether or not playing well late in the season translated into October success for batters. The answer was no, probably not. I compared regular season wOBAs in the months of September and October for batters to their wOBAs in the postseason to see if trends that began at the end of the regular season continued into the playoffs. The numbers indicated that for the last three World Series winners at most four batters continued their late-season trends into October. The rest saw their performances reset, sometimes wildly.

Today I’m examining the key pitchers from the 2009 Yankees, 2008 Phillies and 2007 Red Sox, once again to see if performance from the end of the regular season is in any way a predictor of playoff performance.

Here’s the data:

Once again, the numbers suggest that the old rubric that everything resets in the postseason is true. On the 2009 Yankees, only CC Sabathia continued the trend he established in September into October. Many pitchers on the team improved in the playoffs, but improvement is not a continuation of a baseline. It is a change, and many Yankee pitchers got worse as well. On the 2008 Phillies only Brad Lidge performed at the same (excellent) level from the end of the season through October. A case could be made for Cole Hamels, but he improved his performance by more than one run per game, which is a substantial change from the end of the season. Finally, on the 2007 Red Sox, only Curt Shilling‘s September was a reliable predictor for his postseason. Most of their pitchers actually improved, but their end-of-season play didn’t suggest that their numbers would improve.

There were two motivations to this series of posts. The first was to see if there was any truth to the rumor that postseason baseball is effectively a reset button for the teams who succeed once they get there. By all accounts the answer is yes, for both batters and pitchers.

The second motivation to these posts was to see if there was any silver lining to the Yankees’ recent bad play. At the time of this writing it would take an unprecedented late season collapse to keep the Yankees out of October, but if September is any indicator the Bombers won’t have much mojo once they get there.

The good news is that by all accounts September doesn’t seem to be an indicator. October does in fact seem to be the start of a second season. So long as the Yankees get that last victory they should have as strong a chance to make a run as any other contender.