SAN FRANCISCO -- Josh Collmenter did everything he could to end Arizona's losing streak and reward himself with a career high for wins. He left the game when it was still scoreless.
Oliver Perez could only retire one of the four hitters he faced, and that was all the San Francisco Giants needed to beat the Diamondbacks 5-0 on Wednesday night.
"I walked the first guy and you can't start like that," Perez said. "I tried to work through it and improve. You're going to have these kinds of games over a long season."
After walking Hunter Pence, Perez (3-4) gave up an RBI double to Gregor Blanco, struck out Travis Ishikawa and allowed a single to Brandon Crawford.
Evan Marshall took over and gave up a double to pinch-hitter Matt Duffy and a sacrifice fly to Angel Pagan.
Jean Machi (7-1) retired the only batter he faced for the win, and the Giants remained 2-1/2 games behind the first-place Los Angeles Dodgers in the NL West.
The late scoring surge extended San Francisco's winning streak at home to a season-high eight games.
It also broke up a stellar pitching duel.
"You've got to give credit to Collmenter. He was good," Blanco said. "Good changeup. He was locating the fastball. He was tough to hit. He was keeping us out of balance. After they took him out, we got to the bullpen."
Collmenter pitched six scoreless innings. He struck out three, walked two and has allowed one run or fewer in each of his last four starts. He's still looking for his career-best 11th win despite an 0.65 ERA over his last four starts.
"It seems every time we come in here it's a low-scoring game and I'm trying to keep us in it for as long as possible," Collmenter said. "Unfortunately, they got a couple of timely hits."
With one game remaining on their road trip, the Diamondbacks have scored 17 runs in nine games, nine of them coming in the only two wins. Arizona lost its fifth straight.
"He was great," manager Kirk Gibson said of Collmenter. "I had to take him out with a couple of runners on. We had to try and score a run. We've haven't been doing that."
Collmenter did set a career high for innings pitched with 157 this year. He threw 154-1/3 innings in 2011.
"I haven't been locked in, but I've been effectively wild and made pitches when I needed. The defense made plays behind me," he said.
Gibson held the pitching staff in the dugout afterward to give them a pep talk. "It's tough to lose like that, but that's not what the meeting was about," he said. "It was more about reaffirming what we have to do over these last 18 games and to keep pushing."
Collmenter said the team has meetings like that from time to time as a way to check in. "We take stock of where we're at," he said. "We'd like to get on a roll and have some positive momentum heading into the offseason."
Diamondbacks: RHP Brad Ziegler wound up requiring microfracture surgery on his left knee Tuesday and will likely face a longer rehab than originally thought. Ziegler had planned to have an arthroscopic procedure, but doctors found more damage in the reliever's knee.
Arizona: RHP Randall Delgado (3-3) pitches Thursday afternoon, his second start since April 10. In four games at AT&T Park, he is 1-0 with a 2.25 ERA.
Giants: RHP Jake Peavy (3-4) has made 30 career starts against the Diamondbacks but has faced them just once since 2009. He is 14-12 with a 4.57 ERA against Arizona overall.
