PITTSBURGH (CBS / AP) — James McDonald scattered four hits over seven innings, Mike McKenry homered and the Pittsburgh Pirates edged the San Francisco Giants 3-1 on Saturday.

Neil Walker doubled twice and drove in a run while extending his hitting streak to 11 games and Joel Hanrahan worked the ninth to pick up his 23rd save.

McDonald (9-3) struck out 10 and walked none, winning his fourth straight start and lowering his sparkling ERA to 2.37.

The Pirates have won nine of 11 and are guaranteed at least a share of the NL Central lead through the All-Star break.

Ryan Vogelsong (7-4) couldn’t quite match McDonald, allowing three runs and eight hits in seven innings. Ryan Theriot and Gregor Blanco had two hits apiece for the Giants, who have dropped six of eight.

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