SAN DIEGO (AP) – The only way Barry Bonds got the ball out of the yard was by bouncing a ground-rule double.

Not so for Mike Piazza and Khalil Greene, who homered to lead the defending NL West champion San Diego Padres to a 6-1 win over Bonds and the San Francisco Giants on Monday.

Piazza homered in his first at-bat with the Padres in the second inning and Greene hit a two-run shot into the second deck in left – practically over Bonds’ head – in the sixth. Greene finished with three RBIs.

Bonds did come out swinging, driving the first pitch he saw from ace Jake Peavy into center field leading off the second, missing a homer by about 20 feet. The ball bounced over the fence into the Padres’ bullpen. Bonds scored on Lance Niekro’s two-out single.

Under investigation by baseball for alleged steroid use, Bonds entered the season with 708 homers, needing seven to pass Babe Ruth for second place and 48 to break Hank Aaron’s record. He’s hit 81 off the Padres, his most against any team.

The crowd at Petco Park booed Bonds every chance it got – during pre-game introductions, when he went to left field in the first inning, when he caught Dave Roberts’ slicing liner for the Padres’ first out, when he came to bat leading off the second, when he scored and even when he chased down Adrian Gonzalez’s double in the second.

Bonds finished 1-for-4.

With two outs in the sixth, first base open and a runner on second, Bonds flied out to center.

Piazza tied the game leading off the second by driving a 1-0 pitch from Jason Schmidt over the fence in right-center to tie the game at 1. He signed as a free agent in the offseason after his $91 million, seven-year contract with the New York Mets expired.

Padres rookie Josh Barfield, son of former AL home run champ Jesse Barfield, singled to center leading off the fifth for his first big league hit. He scored his first run on Eric Young’s sacrifice fly to give the Padres a 2-1 lead.

Greene homered with one out in the sixth, with Gonzalez on base with a one-out single. Bonds turned and watched the ball land in the seats. Greene added an RBI single in the eighth, and Vinny Castilla followed with a sacrifice fly.

Peavy got the win by holding the Giants to a run and four hits in seven innings while striking out five and walking one. He led the NL with 216 strikeouts last year.

Scott Linebrink and Clay Hensley completed the five-hitter.

Schmidt went seven in taking the loss, allowing four runs and seven hits while striking two and walking one.

Notes: Heisman Trophy winner Reggie Bush of USC, a San Diego-area native, threw the ceremonial first pitch to Padres rookie Josh Barfield. “Baseball was my first sport,” Bush said before the game. “I wish I would have stayed with it.” Then again, he could be the No. 1 overall pick in the NFL draft later this month. … Bush wore a Padres jersey with his college number, 5, on the back. … The first error of the year was by Padres broadcaster Ted Leitner, during pre-game introductions. Castilla, the Padres’ new 3B who bats seventh, was ready to run onto the field when Leitner instead introduced Barfield, who bats eighth. … Closer Trevor Hoffman and bullpen catcher Mark Merila, who battled a brain tumor last season, raised the 2005 NL West championship banner. … Piazza’s homer was his 398th, tying Dale Murphy for 43rd on the all-time list. He was the ninth player to homer in first at-bat with the Padres. … The Giants had won five straight season openers and seven of eight. It’s the 17th time in 21 seasons they’ve opened on the road.

AP-ES-04-03-06 2144EDT