The wholesale rebuilding of the Athletics continues, though this doesn't make sense. Swisher was a fan favorite, signed to a long-term deal, and about to enter his peak years.
SAN FRANCISCO CHRONICLE (1-3-08):
On Thursday morning, Oakland general manager Billy Beane completed a surprising deal that sent popular outfielder Nick Swisher to the White Sox in exchange for three top-notch prospects.
Last month, the A's sent their best pitcher, All-Star Game starter Dan Haren, to Arizona in a deal that netted them six prospects. On Thursday, the A's moved one of their most consistent offensive performers: Swisher was second on the team with 78 RBIs last season. The previous year, he'd driven in 95 runs and hit 35 homers.
Long a favorite of Beane's and one of the central figures of the book "Moneyball," Swisher was presumed to be one of the untouchables as the A's entered this new phase, a piece to build around rather than to use as bait for new talent. He was getting more expensive, however, after signing a five-year deal worth nearly $27 million last summer. Swisher also turns 28 later this month, and the A's suddenly have a haul of young outfielders.
The A's received outfielder Ryan Sweeney, left-hander Gio Gonzalez and right-hander Fautino de los Santos, who are all ranked among the White Sox's top 10 prospects. Baseball Prospectus recently listed de los Santos as Chicago's No. 1 prospect, Gonzalez No. 2 and Sweeney No. 8.
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http://www.sfgate.com/cgi-bin/article.cgi?f=/c/a/2008/01/03/SP81U8RB6.DTL&tsp=1