SAN DIEGO -- A.J. Pollock is regaining his form right when his team needs him most.
Pollock, who missed nearly two months with a thumb injury, drove a 1-2 pitch from Kirby Yates (4-2) over the wall in left for his 16th homer, sending Arizona to its fourth win in five games. Arizona had tied it at 3 on Daniel Descalso's solo homer off rookie Trey Wingenter in the eighth.
"He threw me a fastball earlier in the count that was right there and I just missed it," Pollock said. "I fouled a couple of pitches and he threw the fastball right there and I was able to do some damage."
After getting two hits and driving in two on Saturday night, Pollock is hitting his stride at an opportune time.
"He's an elite player when healthy," Diamondbacks manager Torey Lovullo said. "We can't do it with just one or two guys, we need everyone and we need A.J. to be A.J."
Archie Bradley (4-4) pitched a scoreless eighth for the win, and Brad Boxberger retired the side in the ninth for his 28th save. The Diamondbacks remained a half-game ahead of second-place Colorado, which won 4-2 at Atlanta.
"We know what the stakes are, we know exactly what's going on in the standings," Lovullo said. "To separate that out and still execute and come out on top is pretty impressive."
David Peralta homered in the third against San Diego starter Brett Kennedy. Peralta missed Friday's game due to illness and was limited to pinch-hitting on Saturday, but he collected two hits in the finale of the four-game set.
"It was huge, and these are the types of games you have to find a way to win," Lovullo said. "To get a solo homer in the eighth and a solo homer in the ninth to win it, it was an exceptional win. "
Arizona slugger Paul Goldschmidt set a club record by reaching base in 10 straight plate appearances when he was intentionally walked in the first. But he struck out on a foul tip in the third.
Hunter Renfroe homered and drove in three runs for San Diego, which has lost seven of its last eight against Arizona at Petco Park.
"A.J. Pollock is a really good hitter, and when you miss your spot to a really good hitter, sometimes you pay the price," Padres manager Andy Green said. "I'm sure he'd like to have that one back."
Renfroe hit a two-run shot in the first against Zack Greinke that travelled into the visiting bullpen in left-center and bounced near the newly erected statue of Padres great Trevor Hoffman. Renfroe was later hit on the right forearm by a pitch from Bradley and exited the game in the ninth.
Greinke allowed three runs and five hits in six innings. He struck out seven and walked one.
"A lot of it was pretty good, but I got behind in some counts in the first inning," Greinke said. "Maybe not too great to start that first inning, but after that it was a lot better."
Kennedy pitched five innings in his third career start, allowing two runs and six hits.
Diamondbacks: RHP Shelby Miller, on the 60-day DL with right elbow inflammation, threw from 60 feet on Saturday and felt no discomfort in his arm. It was the first time Miller has thrown since being shut down in July after making just four starts following his return from Tommy John surgery.
Diamondbacks: After an off day on Monday, Arizona returns home to face the Los Angeles Angels. LHP Patrick Corbin (10-8, 3.18 ERA) takes the mound for the Diamondbacks, facing the Angels for the first time in his career.
Padres: Are off Monday before beginning a three-game series at Colorado. The club has not named a starter for Tuesday's game against LHP Tyler Anderson (6-5, 4.39 ERA) and the Rockies.
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