Marcus Thames homered twice and drove in three runs for the Tigers, who had their season-best six-game winning streak snapped.
Bowker hit a 1-2 pitch into the seats in the right-field arcade, the first batter faced by Rodney after he relieved Freddy Dolsi (0-2) with two runners aboard. The /*Tigers*/ activated Rodney from the disabled list earlier in the day after the setup man had missed the entire season with shoulder problems.
Keiichi Yabu (3-3) pitched the eighth for the win. Fred Lewis homered and added a two-run double in the big eighth inning. /*Giants*/ closer Brian Wilson got into a bases-loaded jam in the ninth in a non-save situation and allowed Curtis Granderson's two-run single. Ivan Rodriguez tripled leading off the seventh and put the Tigers ahead on a disputed play at the plate on pinch-hitter Edgar Renteria's sacrifice fly, but Detroit couldn't hold on for starter Justin Verlander.
Giants manager Bruce Bochy was ejected for arguing the play at the plate.
Right fielder Randy Winn caught Renteria's liner and fired the ball home. Replays appeared to show that catcher Bengie Molina tagged Rodriguez with his glove at the start of his slide. Bochy hurried out to argue with plate umpire Tom Hallion, who didn't wait long to toss the skipper -- his third ejection this year.
Thames had his sixth multihomer game and second this year, the other coming on May 28 at the Los Angeles Angels. The homers were just the fourth and fifth allowed by Giants starter Tim Lincecum this season.
Thames made it a career-best four straight games with a homer when he connected for a two-out solo shot in the second that was the first hit of the night off Lincecum. Thames hit a two-run homer in the fourth for his 12th of 2008, giving him homers on his last seven hits.
Thames stepped into the batter's box to boos in the sixth and grounded out to end the inning.
Lincecum hadn't allowed a home run in six starts and 42 2-3 innings since the Phillies hit two off him on May 10.
San Francisco bounced back from a weekend sweep at home by the Oakland Athletics for just its fourth win in 15 at home.
Lewis hit a tying home run leading off the fifth against Verlander, who struck out seven and walked one in six impressive innings. He allowed three runs and five hits as the Tigers lost for only the 10th time in 43 games against National League teams since the start of the 2006 season.
After Thames' first homer, the Giants tied it in the bottom of the second on shortstop Michael Hollimon's throwing error that got past second baseman Placido Polanco and rolled into shallow right. Rich Aurilia's single in the fourth pulled San Francisco to 3-2, scoring Bowker after his double.
Lincecum, who has won four straight decisions, escaped his first loss since April 29 against Colorado. He allowed more than three earned runs for the first time in 20 starts since Aug. 11 last year against Pittsburgh.
Notes:@ Rodriguez had just his third extra-base hit since May 24. ... Detroit OF Gary Sheffield, sidelined since May 27 with a strained muscle in his left side, was set to start a rehab assignment for Class-A Lakeland. ... Giants RHP Merkin Valdez, on the DL since May 15 with a strained right elbow, traveled to Anaheim to be examined by Angels orthopedist Dr. Lewis Yocum.