Peavy got Bonds to fly out to center field for the second out, then retired the side en route to a 6-1 win over the San Francisco Giants on Monday.
Balsley "walked up and said, 'What do you want to do right here?' " Peavy said. "I said, `I want to pitch to him and get him out.' And Balsley said, `OK.' Mike said, `What do you want?' I said, `Fastball away.' And we made a fastball down and away, and he got out."
The Padres have been burned for 81 of Bonds' 708 career homers, but he didn't hit one Monday. The only time way he got the ball out of the yard was by bouncing a ground-rule double in the second.
"I mean, I just felt like I could make a good pitch and get him out," Peavy said. "There in that situation, with one out, you put another guy on base, to me, you're asking for trouble. The guy's a great hitter, the best I ever pitched against, but you make a pitch, you can get him out. I felt confident in my ability to make that that pitch. I didn't want to put any more guys on base."
Piazza and Khalil Greene homered for the defending NL West champion Padres.
Piazza homered on his first swing with the Padres, leading off 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 RBI.
A fan tossed a syringe near Bonds as he came off the field after the bottom of the eighth inning. The syringe apparently did not have a needle. Bonds picked it up with his glove.
"I just put it off the field so no one would get hurt," said Bonds, who is under investigation by baseball for alleged steroid use.
Bonds did come out swinging, driving the first pitch he saw from 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.
The crowd at Petco Park booed Bonds every chance it got -- during pregame 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.
"I felt fine today," said Bonds, who was 1-for-4.
So the did the Padres.
"It would be hard to put together a better game than we did," manager Bruce Bochy said.
Piazza tied it 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. Piazza signed as a free agent in the offseason after his $91 million, seven-year contract with the New York Mets expired.
"Mike announced his presence," Peavy said.
"It's a big ballpark. He took a little off down over the plate, and I really got great extension on the ball and I was like, `Man, if that doesn't go out, I might have to consider hanging it up,' " Piazza said.
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 O. Young 's sacrifice fly to give the Padres a 2-1 lead.
"It was awesome," Josh Barfield said. "That was a dream come true. It was kind of everything I expected, and more."
Jesse Barfield said he got a little teary-eyed seeing his son wearing No. 29, the same number he wore during his big league career.
"I'm very proud," said Jesse Barfield, who visited the Padres' clubhouse afterward. "He's worked hard to get to this point, and he's here. They showed confidence and faith in him, and he's going to do the same for him."
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.
- Heisman Trophy winner Reggie Bush of Southern California, a San Diego-area native, threw the ceremonial first pitch to 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.
- Josh Barfield got a football autographed by Bush.
- Jesse Barfield admired his son's bats and shoes. "Equipment's so much better these days," he said. The elder Barfield also spoke by phone with his youngest son, Jeremy, a high school star in Texas who went 3-for-3 on Monday, including a game-winning homer.
- Closer Trevor Hoffman and bullpen catcher Mark Merila, who battled a brain tumor last season, raised the 2005 championship banner.
- Piazza's homer was his 398th, tying Dale Murphy for 43rd. He became the ninth player to homer in first at-bat with the Padres.