SAN FRANCISCO (AP) -- Barry Bonds is sidelined by a broken thumb, so the San Francisco Giants are turning to unlikely sources such as Rich Aurilia and Marvin Benard for power.

Aurilia hit a two-run homer, Benard added a solo shot and Joe Nathan became the third straight Giants pitcher to shut down Colorado's suddenly struggling offense as San Francisco defeated the Rockies 4-2 Wednesday.

	Nathan

"I think everybody takes the attitude we have to do more little things to win," Aurilia said. "You're never going to replace a guy like Barry in the lineup."

Bonds, tied for second in the majors with 28 home runs, missed his fourth straight game with a hairline fracture in the tip of his right thumb.

Nathan (5-2), who was battered in a start less than a week earlier at Colorado, allowed two runs on six hits in eight innings.

Nathan's only two losses this season have come at Coors Field in Denver, where he has given up 18 runs in 8 2/3 innings. He has beaten the Rockies twice at Pac Bell Park this year, allowing two runs in 15 innings.

"I guess it's just the field. It just seems like a few more fall in at their place," he said. "They're a different team on the road, like we are."

Felix Rodriguez pitched the ninth for his second save in four opportunities.

Colorado now has lost 11 straight in San Francisco. At Pac Bell Park, which opened this season, the Rockies have three runs in 45 innings. The Giants swept a day-night doubleheader from Colorado on Tuesday, winning 4-1 and 3-0.

"We have to find a way to score more runs," said Colorado's Jeff Cirillo, who was selected along with teammate Todd Helton as an NL All-Star reserve Wednesday. "Part of it is mental. We've had discussions about it and we realize we can't always rely on the home field. I'm a firm believer that hitters will hit no matter where they play."

The Rockies scored their two runs in the seventh, on an RBI double by Darren Bragg and a sacrifice fly by pinch-hitter Terry Shumpert.

Stan Belinda (1-2), who came in at the start of the seventh and failed to get an out while allowing three runs on three hits, was the loser. Starter Pedro Astacio pitched six innings, allowing one run on five hits.

"I hate to waste a performance like that, but Nathan was just as good," Colorado manager Buddy Bell said of Astacio's performance. "He's been our No. 1 guy and he pitched like it."

Helton, who leads the NL with a .389 average, extended his hitting streak to 11 games by going 1-for-3 with a walk.

San Francisco left fielder Armando Rios left the game in the seventh with a bruised left shoulder. Rios turned the wrong way on a ball hit into the gap by Jeffrey Hammonds and ran hard into the wall while trying to catch up to the ball. Hammonds ended up with a double.

Game notes
Colorado's Larry Walker missed the game with a sore right elbow. ... Benard's homer was the 24th allowed by Astacio this season, second worst in the NL. ... The Giants have won five straight. ... Since 1996, the Giants are 25-6 at home against Colorado. ... Belinda blew a save for the sixth time this season. The Colorado bullpen has 12 blown saves overall.