SAN FRANCISCO -- It had been so long since Esteban Loaiza pitched a complete game, he had no idea if he'd ever last nine innings again.
Oakland sent two relievers out to warm up in the eighth inning Sunday -- just in case he couldn't go the distance.
"It feels great," Loaiza said. "I still can't believe it. ... It had been a long time. Two years is like 70 starts."
Bobby Crosby had two RBI and scored twice, Antonio Perez added a two-run double and Jason Kendall finished with three hits. Payton also scored two runs and matched his career high for hits, including a ninth-inning triple.
Barry Bonds left the game after the second inning with irritation in his left knee, a day after connecting for his 719th home run. The seven-time NL MVP had surgery on his left knee after the 2004 season, then underwent three operations on his right knee last year.
Bonds is day to day. He stole second base Friday night and injured the knee sliding -- his only steal this season.
"This is a minor injury," manager Felipe Alou said. "It's not like the chronic right knee that needed all that care last year."
Making his fourth start since coming off the disabled list, Loaiza (7-6) pitched a six-hitter for his 10th career complete game and first since April 18, 2004, for the Chicago White Sox at Tampa Bay. He struck out two, walked one and got plenty of run support as the A's improved to 17-5 in June.
The teams split this year's edition of the Bay Bridge Series, with each club winning three games. Oakland won the finale after Ray Durham rallied the Giants on Saturday with a game-winning, three-run homer.
"It was big," Crosby said. "Yesterday's game was tough. It shows the character of this team to bounce back."
Steve Finley hit his first home run at San Francisco's waterfront ballpark to tie Sunday's game in the fourth, but the A's answered and Loaiza retired his next 10 batters after Finley's fifth homer of the year.
"It's called making an adjustment," A's manager Ken Macha said. "He has the reputation that if you don't get him early, you won't get him."
Finley sent an 0-2 pitch into the arcade seats in right field for his first homer in 257 home at-bats since he joined the Giants in the offseason.
Fans booed when Loaiza walked Bonds on four pitches leading off the second. He scored on Finley's double to left-center two batters later, but was clearly uncomfortable running the bases and hobbled home with a grimace on his face.
Eliezer Alfonzo also doubled in a run to tie the score at 2, then had another double in the seventh.
Bonds, who turns 42 on July 24, was replaced in left field by Mark Sweeney in the top of the third. Backup catcher Todd Greene came in to replace Sweeney at first base, where he started the game.
San Francisco's Matt Cain (6-6), who took a no-hitter into the eighth inning in his previous start, had won five straight decisions. He fell behind in the count against most batters as his pitch count went up in a hurry. He'd already thrown 74 pitches through three innings, but stayed in the game for another 1 1/3 innings before giving way to Brad Hennessey.
Cain, a rookie right-hander, threw a one-hitter against the A's last month in Oakland, a 6-0 win May 21 -- the same day Bonds connected for his 714th home run to tie Babe Ruth for second place on the career list.
Cain gave up two hits and two runs in the first inning this time but bounced back to strike out the side in order on 13 pitches in the second. He walked six and struck out five.
"I was just missing," Cain said. "I got myself in trouble and they capitalized. That's what six walks will do. I was frustrated with myself for not being in the zone more."
The Giants honored Bonds, Jason Schmidt, Moises Alou and Finley before the game for their milestones in the first half of the season. Bonds moved past the Babe; Schmidt matched a 102-year-old club record with 16 strikeouts against Florida on June 6; Alou hit his 300th career home run; and Finley hit his 300th homer on June 14 to make him the sixth member of the 300-300 club for home runs and stolen bases.
Every batter but Loaiza reached base for Oakland. ... A's 3B Eric Chavez was held out of the lineup with tendinitis in both forearms. ... While Moises Alou declared himself ready to play after missing the previous six games with lower back trouble, his father, Felipe, opted to hold the RF out for another game to give him two more days of rest. The Giants are off Monday. ... San Francisco's Kevin Frandsen made his first career appearance at SS in the ninth. Omar Vizquel left early after tweaking his lower back diving for a single up the middle. He is expected to be ready Tuesday.