The Pirates will promote starter John Van Benschoten from Class AAA Indianapolis to pitch Saturday against the Chicago White Sox at PNC Park, manager Jim Tracy said this afternoon.

Shawn Chacon had been scheduled to pitch Saturday, but he will come out of the rotation beginning tonight against the Texas Rangers.

Tracy said the team will not clear space on the 25-man roster for Van Benschoten until Saturday.

Van Benschoten, 26, was 6-4 with a 2.73 ERA in 12 starts for Indianapolis, striking out 45 and walking 30. The Pirates' first-round pick in the 2001 draft, he was in his first full season after surgery on both shoulders in 2004.