Bonds left after the top of the sixth. He played Wednesday night even though the Giants have their home opener Thursday afternoon. The original plan was to play him on Monday and Tuesday, then rest him Wednesday, but Tuesday night’s game was rained out.

Bonds is under investigation by baseball for alleged steroid abuse. The slugger denies using performance-enhancing drugs. He entered the season with 708 homers, seven shy of passing Babe Ruth for second and 48 short of breaking Hank Aaron’s record.

Morris allowed Gonzalez’s homer leading off the seventh, then was chased by consecutive one-out singles by Vinny Castilla and Barfield. Steve Kline retired pinch-hitter Eric Young, walked pinch-hitter Doug Mirabelli to load the bases, then struck out pinch-hitter Mark Bellhorn.

Morris struck out three and walked three.

“I was excited,” said Morris, who spent the previous nine years with St. Louis. “You try to keep all the distractions out, but of course I’m pitching for a new team, pitching for all these guys who are seeing me for the first time during the season. It’s nice to go out there and start strong.”

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Estes allowed three runs and five hits in six innings, struck out four and walked three. Tim Worrell pitched the ninth for the save, getting Young to hit into a game-ending double play with one on. It was the third double play turned by the Giants.

Notes: Padres RHP Woody Williams pitched the seventh. He and Chan Ho Park were put in the bullpen starting the season because the Padres won’t need a fifth starter for the first two weeks. ... Padres 1B Ryan Klesko is debating whether to have surgery on his strained left shoulder, which forced him to start the season on the disabled list. ... Morris was the St. Louis starter on Oct. 8 when the Cardinals beat the Padres at Petco Park to complete a playoff sweep.