BOSTON -- Kevin Youkilis will not be in the starting lineup Thursday night as the White Sox close out a four-game series at Fenway Park. Eduardo Escobar will play third and bat ninth.

Alexei Ramirez is batting second in Youkilis' usual spot.

Rookie left-hander Jose Quintana will start against Red Sox right-hander Clay Buchholz.

Youkilis has 18 RBI in 19 games since coming to the White Sox from Boston in a trade on June 24. It was not immediately known why Youkilis, who had been slowed by back problems earlier this season, is not starting.