SAN FRANCISCO — Now Oakland Athletics rookie Vin Mazzaro knows what it's like to give up a run in the major leagues.

He also knows how small the margin for error is when you're opposing Tim Lincecum.

The Athletics' right-hander mowed through the Giants' lineup early Friday night before allowing three runs in the fifth inning, and that wound up being the difference in a 3-0 loss to the Giants to kick off the three-game Bay Bridge Series.

That cushion was more than enough room for Lincecum (6-1), who tossed his second career shutout and allowed seven hits, striking out eight and walking one.

He also did unexpected damage with his bat, lining a bases-loaded single to break a scoreless tie and ending Mazzaro's career-opening shutout streak at 18 innings, second longest in Oakland history.

The game wrapped in a tidy 2 hours, 2 minutes, as the A's advanced just two runners as far as third base against the defending National League Cy Young Award winner.

"He did a great job tonight," Mazzaro said of Lincecum. "He pounded the zone, he got outs. I guess every time he went out and put up a scoreless inning, I wanted to."

In his third big league start, Mazzaro (2-1) didn't allow a base runner until the fourth or a hit until the fifth. He gave up just the three runs in six innings, striking out four and walking one.

Leading off the bottom of the fifth, Giants first baseman Pablo Sandoval broke up Mazzaro's no-hitter by dropping a bunt down the third-base side and beating it out.

The A's were caught by surprise.

"Sometimes when a no-no is going, guys will do that to break the momentum," A's catcher Landon Powell said. "But we weren't expecting that, that's for sure."

After a fielder's choice grounder, Nate Schierholtz singled and Emmanuel Burriss walked to load the bases with one out for Lincecum. He lined a 2-1 pitch from Mazzaro into center to score Juan Uribe.

"I was trying to go away with a two-seamer and it ran across the middle," Mazzaro said. "He got decent wood on it."

Aaron Rowand followed with a two-run single to left for a 3-0 Giants lead.

Surprisingly, the marquee pitching matchup attracted just 36,035 fans, well short of a sellout at AT&T Park.

The A's had their best chance to score in the fourth. With Adam Kennedy on first with two outs, Jack Cust slammed a double off the wall in right center. A's third base coach Mike Gallego waved Kennedy around third, but the relay throw from Giants second baseman Burris was in plenty of time to nail Kennedy at the plate.

The A's advanced another runner to third in the fifth, but never threatened again against Lincecum.

"He was at 95 (mph) in the ninth inning. I think that speaks for itself," A's manager Bob Geren said. "His curve ball was sharp at times, but his changeup fooled some (of the A's) lefties. He had everything working."

Mazzaro was pulled for pinch hitter Nomar Garciaparra with two outs in the top of the seventh.

Garciaparra, who missed 19 games with a strained right calf, was activated from the disabled list shortly before first pitch. Outfielder Aaron Cunningham was optioned to Triple-A Sacramento.

Geren said he might hold Garciaparra to pinch-hitting duty for the next few games, or perhaps the occasional defensive double-switch. The A's have started a nine-game road trip against National League teams with no DH available.