DETROIT (AP) -- After Rick Porcello allowed an early barrage of hits, about the only thing that could have helped the Detroit Tigers was the weather.
No such luck for manager Brad Ausmus and his team.
"There was some discussion that it might get called because the radar looked really bad," Ausmus said. "Even when we went back out, we were expecting rain in about 45 minutes, but apparently it cleared up."
Jake Peavy pitched six innings without allowing an earned run - even remaining in the game after a rain delay of 2 hours, 42 minutes - and the San Francisco Giants routed Detroit 8-2 on Friday night.
The Tigers trailed 6-0 when a severe storm came through downtown Detroit at the end of the third inning, but once that delay ended, the Giants closed out the game with little difficulty.
Pablo Sandoval homered for San Francisco, which is trying to chase down the first-place Los Angeles Dodgers in the NL West. The Tigers fell two games behind first-place Kansas City in the AL Central - and now trail Seattle by a half-game for the second wild card.
The Giants scored six runs in three innings against Porcello (15-10) before the delay. When play resumed, Peavy (4-4) went back to the mound. He allowed two unearned runs in the fifth, but that was it.
"He was so adamant that he was good to go," Giants manager Bruce Bochy said. "I think it would have crushed him not to go back out there. You just trust Jake."
Playing in Detroit for the first time since winning the World Series there in 2012, the Giants scored a run in the first, three in the second and two in the third. Porcello allowed five earned runs and 10 hits in three innings, and also dealt with an injury scare when a comebacker by Brandon Crawford hit his right foot in the third.
"The ball hit me between the ankle and the heel, and it's sore, but I'll be fine," Porcello said. "It isn't going to be a problem."
Porcello stayed in the game and got the third out of the inning. After the Tigers batted in the bottom half, the rain began in earnest.
Sandoval's solo homer in the sixth - his 16th of the year - made it 8-2.
San Francisco opened the scoring on Sandoval's RBI single in the first, and Travis Ishikawa added one of his own in the second. Angel Pagan's run-scoring groundout made it 3-0, and Joe Panik's infield single brought another run home.
Panik actually made the third out on that play in strange fashion. Second baseman Ian Kinsler's throw got past first base, but catcher Bryan Holaday was backing it up. He threw to first, and Panik - who appeared to have turned ever so slightly toward second after overrunning first - was tagged out.
Saturday's game will start less than 13 hours after Friday's ended, and Ausmus said he sent some of his players home after they were subbed out.
"I told the guys that I took out of the game to go home and try to get some sleep with another game coming so soon," he said.
The game wasn't official yet when the delay started - a fact that was an obvious concern for the Giants.
"If you looked at the radar, it wasn't pretty. We finally got a window there to get things going," Bochy said. "It was a long wait, but well worth it. The last thing we wanted to do was start this thing over."
With debris sailing around in the wind, the Detroit grounds crew overcame difficult circumstances to put the tarp on the field. Head groundskeeper Heather Nabozny injured her right knee and had to have an MRI. The team said she is out indefinitely.
Giants: OF Michael Morse (strained oblique) received a cortisone injection, and the Giants hope he can return for the team's next series, at home against Arizona.
Tigers: RHP Joakim Soria threw off a mound and hopes to throw batting practice Monday as he works his way back from a strained left oblique.
San Francisco will send LHP Madison Bumgarner (16-9) to the mound Saturday. Detroit counters with LHP David Price (13-10), who has a career-high 232 strikeouts this season.