"He's been good all year," Ryan Howard, who had two hits, said of Papelbon. "You can't put it on him."
Crawford snapped a 2-for-22 skid with his two-out hit off the wall in left-center field and finished with four RBIs. Posey, who also doubled and scored in the 14th, had four hits, including two doubles, two runs and an RBI on his homer.
"It was one pitch," Phillies manager Ryne Sandberg said. "He was first-ball swinging."
The Giants (56-44) improved to 8-2 in extra-inning games and 6-0 on the road. The Phillies (43-57) fell to 6-7.
"It's tough right now," Howard said. "It's just how it goes sometimes. It's just not going our way this year."
Hunter Pence had three hits, including a fifth-inning homer. Pence is a lifetime .353 hitter with 14 homers in 34 games against Philadelphia.
Jimmy Rollins hit a two-run homer in the fifth, giving him five homers and 13 RBIs in his last 10 games.
Roberto Hernandez limited San Francisco to three runs on five hits over 5 2/3 innings, walked three and struck out one.
Ken Giles allowed one run in the seventh after entering the game with a 14 2/3-innings scoreless streak.
"His command wasn't as good as it's been," Phillies manager Ryne Sandberg said. "But he hung in there."
Ben Revere had three hits and two stolen bases.
NOTES: Philadelphia is 6-7 in extra-inning games. ... Philadelphia placed outfielder John Mayberry Jr. on the 15-day disabled list Tuesday with left wrist inflammation and recalled outfielder Darin Ruf from Triple-A Lehigh Valley. ... One day after returning from a two-month DL stint because of a strained left elbow, Phillies LHP Cliff Lee felt fine Tuesday. "Some ordinary soreness in his legs," manager Ryne Sandberg said. "Nothing with the arm at all." ... Wednesday night, Phillies RHP A.J. Burnett (6-9, 4.08) opposes Giants LHP Madison Bumgarner (11-7, 3.38) in the third game of this four-game set.