Yesterday, Fangraphs had some fun with ERA estimators and came up with a list of players we can reasonably expect will be better in the second half of the season. Dan Haren was on that list. The reason? Haren has been unlucky in 2010. More batted balls are falling for hits, and more fly balls are going over the fence, despite groundball/flyball/line-drive rates and K/BB figures that are consistent with his career averages. And it’s not like Arizona’s defense has been porous. Every regular player except Adam Laroche has posted near-average or better numbers in UZR and +/-.
The Arizona righty currently has a 4.38 ERA, far above his career 3.68 number, so it’s reasonable to expect Haren will be better in the second half based on all this information above. Except for one thing: he’s never better in the second half. Over Haren’s career, he’s got a 3.29 ERA in the first half and a 4.21 ERA in the second half. His first half batting average on balls in play is .273, while in the second half it’s .324.
There are very few players who consistently appear to be better in one half of a season and worse in another. Haren is one of those players. In every season since 2006 he’s declined sharply in the second half.
So what will it be? Will Haren rebound in the second half? Will he struggle? That’s a question a lot of teams looking to trade for a starter are going to debate.
What do you think?