PITTSBURGH (CBS / AP) -- James McDonald pitched six sharp innings Wednesday night for his first victory of the season, and the Pittsburgh Pirates beat the San Francisco Giants 2-0.

McDonald (1-2) allowed four hits and four walks while striking out three. He lowered his ERA to 7.66 from 10.13.

Mike Crotta, Joe Beimel, Chris Resop and Joel Hanrahan completed the five-hitter. Hanrahan recorded his seventh save in seven opportunities, getting Miguel Tejada to ground into a game-ending double play with runners on first and second.

San Francisco wasted a strong outing by Madison Bumgarner (0-4), who allowed only one run and five hits in six innings with one walk and seven strikeouts. He cut his ERA to 6.17 from 7.79, but the Giants lost for the fifth time in six games to fall below .500 at 11-12.

The announced attendance was 9,048 -- the number of tickets sold -- but the actual turnstile count appeared much smaller. The crowd was held down because the Pittsburgh Penguins and Tampa Bay Lightning were playing across town in Game 7 of their first-round Stanley Cup playoff series.

Both McDonald and Bumgarner had been hit hard in their previous starts, McDonald giving up eight runs in three innings at Florida last Thursday and Bumgarner getting tagged for four runs in 2 2-3 innings by Atlanta last Friday.

However, against the Giants, McDonald looked more like the pitcher who went 4-5 with a 3.52 ERA in 11 starts last season after being acquired from the Los Angeles Dodgers at the July 31 trading deadline.

Chris Snyder and Jose Tabata each singled in a run for the Pirates while Neil Walker and Steve Pearce had two hits apiece. San Francisco's Cody Ross also had two hits.

Walker scored the game's first run in the second inning when he singled, took third on Pearce's double and scored on Snyder's hit into center field. Tabata's two-out single to right field off Guillermo Mota in the seventh scored Brandon Wood, who had singled, and made it 2-0.

San Francisco's best scoring chance came in the second inning when it put runners on second and third with one out. However, McDonald got Tejada and Bumgarner to ground out to end the threat.

The Giants have scored just 14 runs in their last six games while hitting .188.

NOTES: San Francisco INF Mark DeRosa is likely to be placed on the disabled list Thursday because of inflammation in his left wrist, which was surgically repaired each of the last two years. Triple-A Fresno INF Emmanuel Burriss was scheduled to arrive in Pittsburgh late Wednesday night in order to be available to play in Thursday afternoon's game if DeRosa goes on the DL. Slumping Pittsburgh 1B Lyle Overbay was not in the lineup for the second time in three games. He has only one extra-base hit in his last 13 games. Pirates SS Ronny Cedeno was benched a night after failing to run out a groundball in a 3-2 loss to the Giants in 10 innings. San Francisco RHP Ryan Vogelsong is scheduled to make his first major league start since Sept. 29, 2004, on Thursday. Vogelsong's last start came for Pittsburgh.

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