CHICAGO -- Jake Peavy pitched seven solid innings in his fifth start with San Francisco, and the Giants rolled past the Chicago Cubs 8-3 on Wednesday, hours after they won a protest regarding a rain-shortened loss from the night before.
Hunter Pence and Andrew Susac homered, and Travis Ishikawa drove in three runs with pair of doubles among three hits to help the Giants strengthen their hold on an NL wild card spot.
Peavy (2-3) has won two straight after losing his first three starts with San Francisco following a July 26 trade from Boston where he was 1-9.
He allowed 10 hits, struck out eight and walked none. Chris Valaika's two-run homer in the second inning accounted for the only runs against him.
The Cubs' Luis Valbuena added a solo homer and a triple in going 3 for 4.
Struggling starter Edwin Jackson (6-14) was hit hard in just 2 2-3 innings, his shortest outing of the season. He allowed seven runs, eight hits and two walks. Jackson has lost seven of eight decisions.
Before the game, the Giants won their protest filed with Major League Baseball over Tuesday night's rain-shortened loss that was called in the fifth inning.
A problem in getting the tarp onto the field caused unplayable conditions, and the game was ruled a 2-0 Cubs win after a delay of over four hours.
MLB ruled the tarp hadn't been properly put away after its previous use, and therefore there was a "malfunction of a mechanical field device under control of the home club."
MLB said this was the first successful protest since 1986.
The suspended game will be completed on Thursday before the regularly scheduled game between the teams.
On Wednesday, the Giants jumped out to a 4-0 lead in the first inning as five of their first six batters reached base. Ishikawa drove in two runs with his first double to cap the outburst.
Ishikawa doubled in another run in the third and scored on Susac's first career homer as San Francisco opened a 7-2 lead.
Pence led off the fourth against Carlos Villenueva with his 17th homer of this season to make it 8-2.
The suspended game will resume on Thursday with the Cubs batting in the bottom of the 5th inning and leading 2-0. In the regularly-scheduled game, Giants LHP Madison Bumgarner (13-9, 3.14) is slated to face Cubs LHP Travis Wood (7-10, 4.86).
Giants: C Buster Posey was out of the lineup because of soreness in his left hip. Giants manager Bruce Bochy likened it to an unscheduled day off, and expected Posey to be back behind the plate on Thursday.
Posey is batting .278 with 13 home runs. He was replaced by Susac.
Cubs: SS Starlin Castro was a last-minute scratch from the lineup due to a family emergency. The team didn't provide details or say how long he would be out.
LHP Felix Doubront, placed on the DL with a left calf strain on Aug. 1, threw on the side on Wednesday. He is expected to make another rehab start at Double-A Tennessee on Sunday or Monday. Manager Rick Renteria said Doubront, acquired from Boston on July 30, is in line to be recalled and start on Aug. 30 when the Cubs play a doubleheader at St. Louis.