Curse of the HR Derby?

Nowadays, you'll hear players cop out of the HR Derby, claiming that, "it messes up your swing", or something along those lines. I don't see how three rounds of swinging for the fences (essentially a televised round of BP) can pull the plug on the rest of your season, right? Let's find out. Here's what the past nine HR Derby champions have done before and after the Derby.

SAMMY SOSA-2000
G H HR RBI SO BA SLG
Pre-HR Derby 86 103 23 74 97 .305 .574
post-HR Derby 70 90 27 64 71 .338 .711

LUIS GONZALEZ-2001
G H HR RBI SO BA SLG
Pre-HR Derby 87 103 26 66 43 .342 .674
Post-HR Derby 75 95 31 76 40 .308 .701

JASON GIAMBI-2002
G H HR RBI SO BA SLG
Pre-HR Derby 86 100 22 71 63 .318 .602
Post-HR Derby 69 76 19 51 49 .309 .593

GARRET ANDERSON-2003
G H HR RBI SO BA SLG
Pre-HR Derby 92 117 22 78 48 .316 .597
Post-HR Derby 67 84 7 38 35 .313 0.463

MIGUEL TEJADA-2004
G H HR RBI SO BA SLG
Pre-HR Derby 85 107 15 75 28 .311 .506
Post-HR Derby 77 96 19 75 45 .311 .566

BOBBY ABREU-2005
G H HR RBI SO BA SLG
Pre-HR Derby 89 99 18 58 65 .307 .526
Post-HR Derby 73 69 6 44 69 .260 .411

RYAN HOWARD-2006
G H HR RBI SO BA SLG
Pre-HR Derby 84 88 28 71 97 .278 .582
Post-HR Derby 75 94 30 78 84 .355 .751

VLADIMIR GUERRERO-2007
G H HR RBI SO BA SLG
Pre-HR Derby 85 101 14 75 32 .325 .548
Post-HR Derby 65 85 13 50 30 .323 .546

JUSTIN MORNEAU-2008
G H HR RBI SO BA SLG
Pre-HR Derby 95 118 14 68 55 .323 .512
Post-HR Derby 68 69 9 61 30 .267 .481

Only three times did a batter's statistics change noticeably following their victory at the Derby (±3 HR ±.20 BA, in the same direction). One of these times (Sammy Sosa), both numbers increased. Furthermore, I wouldn’t give much thought to Morneau’s drop in numbers, since, throughout his 7-year career, his 1st half hitting numbers are far better than his second half numbers—his 1st half HR total nearly doubles his 2nd half’s, and his BA is 32 points higher before the All-Star break compared to after it. That leaves Abreu as the sole culprit; the only proof that superstitious players have that participation in the HR Derby creates glitches in your swing, and ruins the rest of the season. However, by citing Sosa’s improvement after his Derby victory, Abreu’s drop in offense is basically null and void. One player’s numbers shot up, while another’s plummeted—not a very convincing case. So what is it that has influenced notorious HR hitters like Manny Ramirez and Alex Rodriguez to decline a chance to participate in the HR Derby? Probably arrogance. They don’t want to get shown up by someone whom they consider a lesser hitter. This will sound totally off the mark in Manny’s case, but those sluggers who refuse to put on a show on the eve of the All-Star Game must be taking the game way too seriously. In 1999, when Sosa was asked about his poor showing after the Derby’s first round, he told sideline reporter Stuart Scott that he didn’t care, it doesn’t matter since he was just out there to have a good time. Who could forget Big Papi’s role as towel boy, wiping the sweat away from, and bringing Gatorade to whomever is at bat? That’s what it’s all about. It’s not about winning and defining your legacy. Who’s going to remember if Manny got eliminated after round one of the HR Derby, then went 0-2 in the midsummer classic? Probably no one. So, if you look at the data, there’s virtually no reason anyone should refuse a chance to win the HR Derby.
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