BOSTON -

The Boston Red Sox have traded infielder Kevin Youkilis to the Chicago White Sox for utilityman Brent Lillibridge and right-hander Zach Stewart.

Will Middlebrooks' emergence in Boston made Youkilis expendable after a successful 8 1/2-year run with the Red Sox. The versatile All-Star, who can play both of the corner infield spots, is a career .286 hitter with 133 homers and 563 RBIs.

The AL Central-leading White Sox, who also receive cash in the deal, have been looking for a third baseman with Brent Morel plagued by back problems.

The 25-year-old Stewart is 1-2 with a 6.00 ERA in 18 games with the White Sox this season. Lillibridge, 28, is hitting .175 with two RBIs and seven stolen bases in 48 games.