Mike Yastrzemski reached base twice and scored to help the Giants to their sixth win in seven games.
Casey Schmitt began the rally with a leadoff double. After Jung Hoo Lee popped out, Wilmer Flores lined a single to center.
Bailey, who grounded into a double play and struck out in two of his previous at-bats, then smashed a 1-0 fastball from Jordan Roman (1-4) into right-center field.
Ryan Walker (2-3) retired one batter, with two on in the top of the ninth, to get the win.
Phillies All-Star Kyle Schwarber had two hits, including his team-leading 28th home run.
Schwarber flew out, struck out and was hit by a pitch before homering off Giants reliever Spencer Bivens into McCovey Cove. Brandon Marsh, who singled as a pinch hitter leading off the inning, scored on the play.
Two days after being named an All-Star for the second time in his career, Ray allowed four hits and one run in 5 2/3 innings.
The Giants scored their run on Dominic Smith’s check-swing single in the second. The next batter, Bailey, grounded into an inning-ending double play.
Bailey threw out Schwarber attempting to steal third base in the sixth. It’s only the fourth time in the last 12 steal attempts against him that Bailey has successfully thrown a runner out.
Giants RHP Justin Verlander (0-6, 4.84 ERA) seeks his first win with his new team in the series finale Wednesday. RHP Jesus Luzardo (7-5, 4.44) starts for the Phillies.
