Aaron Hill hit a two-run single in the Blue Jays' five-run fourth inning, Matt Stairs added two RBI and Toronto handed Lincecum his first major league loss and avoided a three-game sweep with a 7-4 victory Wednesday.
Lincecum questioned his poise, one of the characteristics the Giants have long praised.
"I was pretty frustrated and showing it, and that's not something I should be doing," said Lincecum. "I'll talk to some guys and get my head back in it. I always thought that was my best asset. My dad said, 'Don't ever show emotion,' and I did today."
McGowan struck out six in six innings and Toronto won in San Francisco for the first time in six tries, improving to 2-7 all-time against the Giants. He allowed two runs and seven hits with four walks. Former Giant Jeremy Accardo finished for his eighth save in 10 chances.
Lincecum (2-1), the Giants' top draft pick in 2006 at 10th overall and nicknamed "Franchise" by his teammates, went 3 2/3 innings for his shortest outing.
"I wasn't even close to the zone with most of my balls," Lincecum said. "Up, down, all over the place."
Lincecum got his first major league hit, as did catcher Guillermo Rodriguez and reliever Jonathan Sanchez. The last time three players on the same team collected their first career hits on the same day was Sept. 20, 1998, by Atlanta's Mark DeRosa, Wes Helms and Bruce Chen at Arizona, according to the Elias Sports Bureau.
The last time it happened when September roster expansion wasn't in effect was April 19, 1962, by the expansion Houston Colt .45s at Wrigley Field. According to Elias, Johnny Weekly, Pidge Browne and Merritt Ranew all got their first hits.
The right-hander was tagged for seven runs and seven hits, striking out six and walking four. He lasted 4 1/3 innings in his last outing and also in his first start, May 6 against Philadelphia. The rookie sensation got his first major league hit when he lined a low pitch for a leadoff double to left in the third.
"I was glad he came out when he did," Hill said. "He's a little guy but man he throws that ball hard. Some guys are up there 96, 97 but you see it. With him, sometimes it looks like it's coming from behind his head and it's just hard."
Barry Bonds, who hit his 747th home run Monday night to move within eight of Hank Aaron's record, pinch hit and struck out swinging with a runner on second for the game's final out. The San Francisco slugger will essentially have two full days of rest before serving as the designated hitter against Boston all weekend in the club's first trip to Fenway Park since playing the Boston Braves in 1915 as the New York Giants.
Accardo was ready to see No. 25 in the ninth.
"I knew it. I peeked in there the previous at-bat and saw him getting ready," Accardo said of facing Bonds. "I've heard that roar quite a bit. You always want to get out there and do your job. It was nice to face him the way the outcome was. It just as easily could have gone the other way with him."
Rodriguez drove in two runs in his major league debut, starting at catcher for the Giants after 11½ years in the minor leagues. He hit an RBI single in the fourth for his first big league hit and added an eighth-inning sacrifice fly.
The Giants won their first home series since taking all three from Houston from May 21-23. They were swept in the previous two series in their waterfront ballpark -- by Colorado and Oakland.
San Francisco reliever Vinnie Chulk left the game because of a bruised right forearm after stopping Phillips' liner leading off the fifth for his only out. After the game, Chulk said the swelling had gone down significantly with ice and hoped to be available Friday.
Sanchez added an RBI double in the sixth and San Francisco added two runs in the seventh on Kevin Frandsen's groundout and Rodriguez's sacrifice fly.
Rodriguez's family got to see the game on TV in his native Venezuela. His dad began to doubt whether the catcher would ever reach the top level.
"I said: 'Just wait. One day I will get my shot,"' he said. "I don't want to say I was nervous, but I had a little bit of butterflies the first two innings. I waited a long time for this day. It was my debut and I think I did it right."
- The Giants' Ryan Klesko also left the game early with soreness in both hips. He hopes to play Friday.
- Randy Winn was back in San Francisco's starting lineup after being held out a night earlier because of a sore ribcage.
- Hall of Famers Juan Marichal and Dave Winfield were picked Wednesday to manage in the All-Star Futures game on July 8 in San Francisco. Marichal, a nine-time All-Star who spent 14 seasons with the Giants, will manage the world team. Winfield, a 12-time All-Star, will lead the U.S. team.
- Blue Jays pitcher A.J. Burnett, who left his start Tuesday night with a mild right shoulder strain, had an MRI and it was determined he won't need a stint on the disabled list.