
In the past twenty years there have been 11 players that were either 1st or 2nd place in the Derby that had single digit home-runs in the second half of that season. Those players are: Jose Bautista (2012), Hanley Ramirez (2010), Justin Morneau (2008), Alex Rios (2007), David Wright (2006), Bobby Abreu (2005), Ivan Rodriguez (2005), Garret Anderson (2003), Jeromy Burnitz (1999), Jim Thome (1998), Ken Griffey Jr. (1994). That means that 27.5% of the players in the top 2 the last twenty years have dropped off in the power category in the 2nd half. Seems like pretty convincing evidence right? Well hang on a minute.
In that same time frame 9 players have equaled or outperformed their HR numbers from the first half of the
season. Prince Fielder ('12, '09), Ryan Howard (2006), Miguel Tejada (2004), Sammy Sosa ('01, '00), Albert Belle (1995), Juan Gonzalez (1993), Ken Griffey Jr. (1993). So 22.5% of those 40 players outperformed or equaled their numbers. This theory is starting to spring some holes.

You may say okay Ryan, but there's still more players that have had bad second halves than good ones. Okay you are correct, but let's look a little further. Four of those under-performing players got injured in the second half and played 50 games or fewer. (Bautista, Burnitz, Thome, and The Kid). So let's ignore their second half power outages. Furthermore, Ivan Rodriguez entered the All-Star Break in 2005 with 6 HR in 74 games and then hit 8 HR in 55 games in the second half. So he probably shouldn't be counted in the theory either. There's five of the eleven players removed.
Now for the tough cases, (Ramirez, Morneau, Rios, Wright, Abreu, Anderson). Ramirez played 56 games in the second half of 2010 hitting .300 with 8 HR just one point below his first half batting average (.301). Justin Morneau (2008) hit 9 HR in 68 games (13.2% HR/Game Rate) versus only 14 HR in 95 games (14.7% HR/GM). Alex Rios after hitting 17 homers in the 1st half hit just 7 after the break, but his batting average rose 16 points from .284 to .300.
David Wright's 2006 season is probably the second most pointed to example of this theory so let's take a look at that. Wright hit .316 with 20 dingers in 87 games before All-Star Week and .305 with 6 homers in 67 games in the second half. This case seems to hold water. Although looking at Wright's splits from that it doesn't look like as big of a slump.
We're going to skip Abreu (don't worry I'll get there, it pains me as a Phillies fan) and go to Garret Anderson. Anderson hit 22 round trippers in 92 games with a .316 BA and after the derby hit 7 HR in 67 games with a .313 BA. That seems like a power outage but consider that the 29 total home-runs that year was tied for the second highest total of his career.

After looking at all of the stats and the breakdown, it seems like there are only two real cases for this curse in the 1st and 2nd place finishers in the past 20 years. And one (Wright 2006) is debatable. So for all of you A's fans out there (quietest fan base in the country?) don't worry about Yoenis. Same for you zombie-Expos...I mean Nationals fans. Your boys should be just fine this year and if not, well just re-watch this you'll feel better. (Spanish version was best I could find)