"Three walk-offs in a row, sometimes you don't see that in a month," said interim manager Ryne Sandberg, who is 5-3 and has seen his team win five of its last six.
Pinch-hitter Cody Asche opened the ninth inning with a single off Heath Bell and advanced to third on Jimmy Rollins' hit-and-run single to right.
Asche wasn't thinking of a walk-off win when he came to the plate, just getting on base.
"When leading off, you have to calm yourself down, know you have to do your job - leading the inning off and setting your team up for a little rally," Asche said.
With runners at the corners and no outs, Michael Young was intentionally walked to load the bases. Kevin Frandsen then struck out.
Bell was replaced by lefthander Eury De La Rosa, who walked Utley to end it.
This was yet another game in which the Phillies had to come back, although they did strike first.
Darin Ruf hit his 10th homer of the season, to center off lefthander Wade Miley, and gave the Phillies a 1-0 second-inning lead. It was Ruf's eighth home run in August.
Arizona scored three runs in the fourth inning, but typical of starter Cole Hamels' luck this season, he was snakebit by a catchable fly to left field that Domonic Brown never saw.
Adam Eaton was hit by a pitch to lead off the inning and Paul Goldschmidt hit a fly near the left-field line.
Brown lost it in the twilight and the ball dropped in for a double, putting runners on second and third.
"It is the kind of tough part of baseball but you have to keep paring down and getting guys out," Hamels said of the lost ball.
Martin Prado then hit a two-run double to left-center.
Prado went to third on a groundout and scored on an RBI single by Matt Davidson.
The Phillies tied the score in the sixth on Carlos Ruiz's two-run double. Over his last 19 games, Ruiz is batting .373 (22-59) with five doubles, two home runs, and seven RBIs.
Hamels threw seven innings before being pinch-hit for by Rollins. B.J. Rosenberg and winning pitcher Jonathan Papelbon threw scoreless innings, continuing the bullpen's recent stellar effort.
With the score still tied, Brown hit a one-out single in the eighth inning, but was caught stealing for the second out. That became a huge play after Ruiz and Ruf hit consecutive singles, putting runners on first and second. John Mayberry Jr. struck out to end the inning.
But the Phillies ended matters in the ninth, which is quickly becoming their favorite inning.
Contact Marc Narducci at firstname.lastname@example.org. Follow @sjnard on Twitter.