Update 1/16 15:42: The deal is official according to Jon Morosi of Fox Sports.

Update 17:50: Slusser Tweets: The minor-league prospect going to the A’s is Double-A infielder Eric Sogard, according to a San Diego source.

Update 16:59: Slusser reports that the deal is 99 percent done and Hairston is thrilled to be going back to San Diego.

Hairston got a call from Kouzmanoff earlier who said that he was going to Oakland. “Yeah! We get to be teammates again,” Hairston said with a laugh. “Then I found out it’s me going to San Diego.”

16:29: Susan Slusser of the The San Francisco Chronicle reports that the A’s have acquired Kevin Kouzmanoff and a prospect from the San Diego Padres for Scott Hairston and Aaron Cunningham.

Team	Acquires
Athletics	3B Kevin Kouzmanoff INF Eric Sogard
Padres	OF Scott Hairston OF Aaron Cunningham

It’s been rumored throughout the Winter that the Padres wanted to trade Kouzmanoff. Kouzmanoff, 28, hit .255 with 18 home runs while driving in 88 RBIs in 2009.

Hairston, 29, is going back to the team that traded him last summer. The Padres traded Hairston to the A’s last July for Ryan Webb and Craig Italiano. Hairston hit 17 home runs and drove in 64 RBIs with the Padres and A’s last season.

Cunningham, 23, played 23 games for the A’s in 2009 where he hit .151 (8 for 53) with 1 home run and 6 RBIs.