David Aardsma #53 of the Boston Red Sox reacts as he is about to get pulled from the game against the New York Yankees on September 26, 2008 at Fenway Park in Boston, Massachusetts.  (Photo by Elsa/Getty Images)The Boston Red Sox announced this afternoon that they have traded reliever David Aardsma to the Seattle Mariners for left-handed pitcher Fabian Williamson. Aardsma was recently designated for assignment when the Red Sox added 1B/OF Mark Kotsay to the 40-man roster.

In 77 appearances out of the bullpen last year, Aardsma was 4-2 with a 5.55 ERA. Williamson was a 20th round draft pick of the Mariners back in 2006 out of Kennedy High School in Sun Valley, CA. He was 4-3 with a 3.10 ERA in 11 starts for Class-A Pulaski and is 10-5 with a with a 3.55 ERA and 144 strikeouts in 124.1 innings.