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Barry Bonds rounds the bases after hitting his 735th career home run on Wednesday, moving him within 20 of Hank Aaron's all-time record.

Marcus Giles hit a two-run homer in the fifth among his three hits and Khalil Greene added a solo shot in the inning for San Diego, which beat the Giants 7-0 in the season opener for both clubs Tuesday — the first opening-day shutout by the Padres in franchise history. Gonzalez homered deep into the right-field arcade off Jack Taschner, who relieved loser Brad Hennessey (0-1).

“I completely blew that spot,” Taschner said. “I let the team down with one pitch. A guy like Gonzalez, he’s not going to let mistakes like that pass.”

The Giants tied it in the bottom half of the fifth on Pedro Feliz’s RBI single, then Randy Winn blooped a single to left to chase Young and put runners on the corners for pinch-hitter Ryan Klesko.

Cla Meredith (1-0) walked Klesko to load the bases but Dave Roberts, who tripled and scored in the third, grounded out to second. Trevor Hoffman pitched the ninth for his first save, and the 483rd overall for baseball’s career leader.

Bonds isn’t ready to concern himself with his team’s 0-2 start.

“One pitch got us,” he said. “It’s nothing to worry about.”

Giants starter Matt Cain pitched six solid innings and allowed five hits and three runs, struck out six and walked one. Cain is beginning his second full big league season after a standout rookie campaign last year in which he led NL rookies with 13 wins and also had a rookie-high 179 strikeouts.

Young gave up three runs on six hits in 5 2-3 innings, struck out four and walked three and kept his unbeaten road streak alive. The right-hander went 6-0 with an NL-best 2.41 ERA on the road last season in 15 starts and is 9-0 with 16 no-decisions in his last 25 starts away from home dating to June 25, 2005.

“It’s luck, I’m telling you guys,” Young said. “I try to think the same way at home as I do on the road. This game is simple. It comes down to execution.”

Notes: Last year, it took the Padres until May 3 for a three-homer game. ... Bonds didn’t hit his first 2006 home run until April 22 at Colorado, his 13th game, 50th plate appearance and 31st at-bat. ... Bonds has 1,375 career RBIs, 13 shy of Willie McCovey’s San Francisco record of 1,388. ... Roberts hit a career-best 13 triples last season. ... Gonzalez finished 3-for-4. ... The Padres will try for a three-game sweep Thursday.