Yonder Alonso scored the winning run when San Francisco second baseman Marco Scutaro couldn't come up with Nick Hundley's grounder, lifting the San Diego Padres to an 8-7 victory in 12 innings over the Giants on Saturday night.
Alonso reached base with his third double of the game, went to third on Jedd Gyorko's single and scored on Scutaro's miscue. The loss is the Giants' fourth straight, and their third extra-inning defeat in four games.
Sergio Romo (1-2) took the loss.
Joe Thatcher (1-0) pitched the 12th inning giving up two hits for the win.
San Diego trailed 5-0 before rallying for six runs in the fourth inning. Alonso and Chris Denorfia each had two-run doubles to chase Barry Zito. Zito gave up six runs - five unearned in 3 2-3 innings. He had four strikeouts and walked one. Disappointment has been common for Zito in Petco Park. He hasn't made it through the fifth inning in five of his last seven starts in San Diego, and hasn't won there since Aug. 2, 2008.