Days after having to trade Jake Fox to the Baltimore Orioles after designating him for assignment, Oakland traded Eric Patterson to the Boston Red Sox after designating Patterson for assignment. Both Fox and Patterson were out of options.
Williamson is a 21-year-old California native who was pitching in the High-A Carolina League at the time of the trade. Williamson was originally drafted by the Seattle Mariners in 2006, but was traded to the Boston Red Sox for David Aardsma before the 2009 season.
The 6'3'' southpaw came into this season with a 3.02 ERA and 248 strike-outs in 232.1 innings. He had walked more than four batters per nine innings during his career, but he had allowed only 12 homeruns. He went 10-5 with a 2.42 ERA in 108 innings in the Sally League last season.
This season, Williamson was pitching at the High-A level for the first time. In 14 starts for the Salem Red Sox, he had a 4-3 record and a 3.72 ERA. His K:BB ratio was an unimpressive 40:34, but he was inducing two groundouts for every flyout and had allowed only three homeruns. He is likely to be assigned to High-A Stockton.
Saturday marked the end of Patterson's run with the A's after nearly two years with the club. He was acquired by Oakland in July 2008 from the Chicago Cubs along with Matt Murton, Josh Donaldson and Sean Gallagher for Rich Harden and Chad Gaudin. In one-plus seasons with the Triple-A Sacramento River Cats, Patterson was brilliant, batting .311 with 16 homers and 51 stolen bases over 135 games. However, he was unable to duplicate that success with Oakland.
Patterson was acquired by the Red Sox to give the team depth in the infield after they lost second baseman Dustin Pedroia to a broken foot. Patterson has primarily been a second baseman throughout his minor league career but had been used by the A's as an outfielder for most of the 2010 season. He was batting .204 with four homers and six stolen bases in 103 at-bats for the A's at the time of the trade.