The Athletics have acquired reliever Sandy Rosario from the Red Sox for a player to be named later or cash and designated outfielder Jermaine Mitchell for assignment.

Rosario, 27, has thrown just 7.2 MLB innings with a 15.26 ERA. He spent the bulk of 2012 at Triple-A New Orleans in the Miami system, posting a 1.04 ERA with 24 strikeouts against just two walks in 26 innings. The Red Sox claimed Rosario off waivers on Oct. 17.

Mitchell, 28, has yet to appear in the major leagues. He spent 2012 at Triple-A Sacramento for the Athletics, where he hit .252/.345/.386 with six home runs in 108 games.

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