As a result, Cincinnati won its first road series since taking two of three from the Cleveland Indians from June 26-28, and did so against a team in the National League Wild Card hunt.
"It's a series that you think that we should win," Giants starter Matt Cain said. "We just didn't get it done. Our pitching let us down."
The Reds' lineup became just the third all season to score five times against Cain (12-4). Brandon Phillips' first-inning solo home run off the All-Star right-hander was a sign of things to come.
Filling the capable cleats of Scott Rolen (post-concussion symptoms), Adam Rosales smacked a two-run blast in the fourth, extending Cincinnati's advantage to 4-0. Young Wladimir Balentien extended the Reds' lead to five with an RBI single in the fifth.
It all resulted in Harang's first "W" since May 25. The 31-year-old right-hander allowed both Giants runs on seven hits over seven innings. He struck out seven.
"I go out there every time, trying to give us a chance to win, and the guys came out, put some runs on the board early," Harang said. "That puts your mind at ease, lets you relax and throw your game."
Winless in his previous 13 outings entering Sunday's start, Harang said he altered his mechanics -- specifically, separating his hands at the top of his delivery faster and keeping his body behind the ball longer -- to increase the zip on his fastball and sport a consistent arm slot. He employed his improved location and the increased velocity on his heater -- his last pitch in the eighth inning was measured at 90 mph -- to induce two Giants double-play groundouts.
With a four-run cushion in the eighth, Harang yielded three straight base hits to start, bringing Pablo Sandoval (the potential game-tying run) to the plate with no outs. Reliever Nick Masset, who will fill the setup role left vacant by the trade Sunday of David Weathers, replaced Harang and induced a third ground-ball double play. San Francisco left the frame with just one run.
Closer Francisco Cordero earned his 24th save with a clean ninth to wrap up Harang's much-awaited win.
"Boy, it's been a long time for Aaron," manager Dusty Baker said with a sigh. "Sometimes when you don't have a victory for a long time, you start wondering, 'Am I ever going to win again?'"