Michael Wacha pitched seven shutout innings and drove in two runs as the St. Louis Cardinals routed the Pittsburgh Pirates 9-2 Sunday for a three-game sweep.
The Cardinals outscored Pittsburgh 26-10 overall in taking the NL Central lead.
The Pirates arrived at Busch Stadium this weekend with a 1½-game division lead and a chance to cement their first winning season since 1992.
They left trailing the Cardinals by 1½ games and still stuck on 81 victories.
Wacha (3-0) allowed two hits and walked two, both of which were erased on double plays.
He struck out two and never had more than one runner on at a time.
Pittsburgh starter Charlie Morton (7-4) left with discomfort in his left foot in the second inning.
He allowed five runs on six hits and two walks in 1 2-3 innings.