The Home Run Derby Does Not, in Fact, Screw Up a Guy's Swing

It's inevitable.  One of the participants in this year's contest will go into a slump.  And the first thing people will blame is the Home Run Derby, thinking that somehow his mechanics have been thrown off by what amounts to taking extra batting practice.  Fangraphs' R.J. Anderson recently did a pretty thorough debunking of this popular myth.  He selected the five participants in recent history who have seen the most significant decline in power numbers in the second half, and concluded that most of them were simply playing above their heads and were bound to come back down to earth eventually.  And that makes sense.  The event organizers for the Home Run Derby invite players who, naturally, are hitting a lot of home runs.  These players are often having a really great first half of the season and are putting up numbers that just aren't sustainable.  Bobby Abreu is probably a perfect example.  He was having a pretty good first half of the season, hitting .307/.428/.556/.955 with 18 home runs and putting up career numbers in nearly every offensive category.  Then he started to cool off after the All-Star break, hitting only six more homers through August and September.  Obviously, people (including Abreu himself I believe, but I'll get to that in a minute) blamed the Home Run Derby for his perceived slump.  However, Abreu finished the season batting .286/.404/.474/.879, which is essentially right in line with his career numbers.  What we were seeing wasn't really a slump so much as regression: that is, his production starting was to fall right back in line with his career averages (or, if you prefer, he was who we thought he was).  I think it's also worth noting that Abreu was 34 years old at the time, and those numbers are about what you would expect from a player his age.

If you're not into fancy statistical analysis, then perhaps Joe Morgan (of all people) says it best:

"All players get tired in the second half. That is why very few players hit more HRs in the second half."

Which leads me to Joe Mauer.  Mauer was red-hot in his first month since coming off the DL, batting .414/.500/.838/1.338.  He's hit 15 homers already this season, two more than his career mark set in 2006.  These numbers aren't sustainable for anyone, especially not a catcher, and he's just bound to cool off eventually.  In fact, he already has, batting *only* .325/.404/.425/.829 in the month of July.  He'll probably finish the season batting .326/.414/.487/.901, which is much closer to his career average and might still be enough to earn him his third batting title.  SO I DON'T WANT TO HEAR ONE GODDAM THING ABOUT THE HOME RUN DERBY MESSING UP HIS SWING.

And yet, the idea that participating in the Home Run Derby causes hitters to slump persists.  Players are always quick to use it as an excuse, probably because it sounds a lot better than: "Sorry guys, I'm just tired.", or "I guess my power numbers are simply regressing to the mean."  Both of those are probably much closer to the truth, but nobody really wants to hear it.