AccuScore: Curse of the Home Run Derby

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Each year, fans look forward to the Home Run Derby even if managers of the competing players often cringe. While the derby usually lights up the night, statistics show it is the catalyst for a second-half power outage.

It is easy to say the derby has an adverse effect because players alter their natural swings to hit more home runs. Statistically this is hard to prove, but Bobby Abreu’s(notes) second-half collapse in 2005 got us thinking.

Bobby Abreu won in 2005.
(Getty Images)

Abreu’s record of 41 derby home runs should have been a prelude to a huge second half. Instead, it seemed like a curse that plagued him for the rest of the year. He finished with only six homers after the break, highlighting a negative trend that sees derby contestants struggling for the remainder of that season.

In looking at the 40 finalists and semi-finalists over the past 10 years, statistics show 60 percent of players saw a decrease in slugging percentage. Of those 24 players, nine suffered what can be considered a major loss of power (-0.100 in slugging percentage). In comparison only two players gained that much in slugging percentage.

Slugging Percentage
Year Name 1st Half 2nd Half Difference
2002 Sammy Sosa 0.641 0.536 -0.105
2006 David Wright(notes) 0.575 0.469 -0.106
2005 Bobby Abreu 0.526 0.411 -0.115
2001 Luis Gonzalez 0.745 0.62 -0.125
2003 Garret Anderson(notes) 0.597 0.463 -0.134
2009 Albert Pujols(notes) 0.723 0.582 -0.141
2003 Jim Edmonds(notes) 0.668 0.507 -0.161
2002 Paul Konerko(notes) 0.571 0.402 -0.169
2008 Lance Berkman(notes) 0.653 0.436 -0.217
Average .562 .432 -.130


Players chosen for the Home Run Derby are top hitters from the first half of the season (this season captains were named to select the AL and NL sides). Some players have been invited on the strength of a great first half of the season. These are the players who fit the profile for a substantial decline in the second half.

If you are going to take this kind of look at the Home Run Derby participants, it is also necessary to look at the sluggers that did not compete. AccuScore looked at the top five home run hitters who did not participate in the derby for each of the past 10 seasons. A whopping 70 percent of those players actually improved their slugging percentage after the All-Star break.

Slugging Percentage
Year Name 1st Half 2nd Half Difference
2004 Albert Pujols 0.599 0.721 0.122
2003 Alex Rodriguez(notes) 0.544 0.679 0.135
2007 David Ortiz(notes) 0.556 0.695 0.139
2001 Richie Sexson 0.476 0.625 0.149
2008 Carlos Delgado(notes) 0.455 0.606 0.151
2001 Shawn Green 0.527 0.682 0.155
2010 Jose Bautista(notes) 0.543 0.702 0.159
2002 Jim Thome(notes) 0.604 0.773 0.169
2008 Manny Ramirez(notes) 0.518 0.723 0.205
Average 0.535778 0.689556 0.153778

The Home Run Derby curse is real. Since 2001, derby participants have averaged a .025 decline in slugging percentage. The top home run hitters who did not participate averaged a .036 increase in slugging.

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Updated Sunday, Jul 10, 2011