MIAMI — Rudy Seanez intentionally walked Barry Bonds to load the bases in the 10th inning, then couldn't throw a strike when he needed one.
Pinch-hitter A.J. Pierzynski walked on four pitches to force in the tiebreaking run, and the San Francisco Giants beat the Florida Marlins, 6-5, Wednesday night.
San Francisco's Pedro Feliz hit a two-run homer off Guillermo Mota to tie it at 5-5 in the eighth.
The Giants' winning rally in the 10th began when Ray Durham reached with one out on an infield single against Seanez (1-1). Deivi Cruz also singled for his third hit, and after Feliz popped out, Bonds was walked intentionally for the third time to load the bases.
Pierzynski then forced in the run, with the final pitch from Seanez in the dirt.
Jim Brower (7-6) pitched two scoreless innings for the win. Converted starter Dustin Hermanson pitched a hitless 10th for his sixth save in seven chances.
With the victory, the Giants moved to within four games of the first-place Dodgers in the West Division. They also remained one game behind wild-card leader Chicago. The Marlins, who had won their last three, fell six back in the wild-card race.
Florida lost despite a big game by Juan Pierre. He went three for four with a walk, stole three bases, scored twice and drove in two runs.
San Francisco pulled even when Feliz hit his 18th homer after Cruz reached on an infield single.
Cruz hit his fifth homer leading off the sixth against Dontrelle Willis.
National League batting leader Bonds was hitless in two at-bats, was caught stealing after another walk and struck out for only the 25th time this season. But an intentional walk to him backfired in the fourth, helping the Giants take a 2-1 lead.
Willis retired the first two batters, then put Bonds on. Edgardo Alfonzo also walked, and after both runners advanced on a passed ball by Paul Lo Duca, Marquis Grissom singled home the unearned run.