Padres 2, Phillies 1: Jesus Guzman's pinch-hit sacrifice fly plated Cameron Maybin in the seventh inning and Edinson Volquez tossed six solid frames as visiting San Diego defeated Roy Halladay and struggling Philadelphia.

Will Venable had a pair of hits - including an RBI double in the third inning - for the Padres, who defeated the Phillies for just the fourth time in 18 outings.

Halladay (3-3) failed to record a win in his fifth straight start, despite striking out 10 in seven innings. The two-time Cy Young Award winner hasn't earned a victory since April 16.

Halladay got into trouble in the seventh as Maybin ripped a leadoff double to right center and advanced to third on John Baker's single. After Halladay struck out Jason Bartlett, Guzman lifted a sacrifice fly to right to bring home Maybin and give San Diego a 2-1 lead.

Volquez (2-2) won his second straight start after allowing just one run on six hits in six innings. Two relievers bridged the gap to Dale Thayer, who stranded Jimmy Rollins at third base in the ninth for his third save.

Shane Victorino collected three hits and rookie Freddy Galvis had an RBI double for the Phillies, who have dropped four of their last five games.

GAME NOTEBOOK: Halladay suffered his second loss of the season to San Diego. Philadelphia has lost the last five games started by Halladay. ... Volquez improved to 3-1 in his career versus the Phillies. ... San Diego's Yonder Alonso went 1-for-3 to extend his hitting streak to nine games. ... Philadelphia's Ty Wigginton left nine men on base.