The A's bumbled their way through much of their marathon with the Giants on Saturday, then nearly staged a comeback for the ages.

Trailing by five runs to start the ninth inning, they batted around in a four-run rally before falling 9-8 in one of the wilder finishes in the history of the Bay Bridge interleague series.

Jemile Weeks came up with the bases loaded and two outs in the ninth against Clay Hensley, the Giants' fourth pitcher of the inning. Weeks lofted a shallow fly toward right-center, but second baseman Ryan Theriot made a running catch for the final out to end the 4-hour, 15-minute contest.

"When you're down, you have to keep grinding, and we did," A's manager Bob Melvin said. "It's too bad we didn't win."

The A's couldn't overcome poor defense and more shoddy work from the bullpen before a standing-room-only crowd of 36,067 at the Oakland Coliseum.

They committed four errors, three by first baseman Brandon Moss in the sixth inning alone, when the Giants scored four runs to command a 6-4 lead.

That tied a major league record for most errors by a first baseman in an inning. It was last done by St. Louis' Jack Clark on May 25, 1987.

"You've got to give him a little bit of a pass," Melvin said of Moss, a converted outfielder. "He's working pretty hard. He's been good to this point. He just had a tough game."

Left fielder Jonny Gomes misplayed a ground single by Pablo Sandoval in the second that allowed the Giants' first run to score.

The A's ninth-inning rally began with RBI singles by Brandon Inge and Derek Norris, who collected his first big league hit earlier in the game. Brandon Hicks, who was called up from the minors Saturday and started at shortstop, delivered a bases-loaded, ground-rule double that scored two and pulled the A's to within a run.

Had the ball not bounced over the left-field wall, Moss probably would have scored from first with the tying run.

It was quite the A's debut for Hicks, likely to play shortstop against left-handed pitchers in the coming games.

"It was exciting," Hicks said. "To battle back there in the ninth inning, it shows a lot of heart. It just didn't work out."

It wasn't quite so memorable of an inning for Weeks. He made the first and last outs of the ninth.

The A's defensive miscues helped erase the encouraging things they did early.

Josh Reddick's two-run homer gave the A's a first-inning lead. After the Giants tied it in the top of the second, Reddick singled home Coco Crisp in the bottom half to put Oakland up 3-2.

Gomes' homer in the third made it 4-2, but the wheels would come off in the top of the sixth.

With runners on first and second, Moss let Sandoval's sharp grounder kick off him for an error. As he chased the ball down the right-field line, he lost his footing and knocked the ball farther away.

Two runs scored on the double error to make it 4-4. Melvin pulled starter Tyson Ross in favor of Jerry Blevins, and Brandon Belt knocked Blevins' first pitch for a two-run homer that put the Giants ahead 6-4.

Moss later dropped a throw from Blevins on a comebacker for an error, but that didn't affect the rest of the inning.

Over the first two games of this series, the A's bullpen has pitched 62/3 innings and allowed eight earned runs and seven walks.

Ross -- called up to start in place of Bartolo Colon, who went on the disabled list as expected -- went 51/3 innings and gave up four hits, four walks and five runs (just three earned).

  • Brandon McCarthy was scratched from Sunday's start because his troublesome right shoulder is hurting again. McCarthy tried playing catch before the game but cut the session short, talked briefly with Melvin and headed for the clubhouse.

    Right-hander A.J. Griffin is expected to start in McCarthy's place for his major league debut. Griffin, who began the season at Double-A Midland, was scratched from Sunday's start with Triple-A Sacramento.

    "It sucks," said McCarthy, who has missed significant time with shoulder issues throughout his career. "The last two weeks have been about the most mentally harrowing as I've had in my career. ... You just kind of want to pull your hair out."

    McCarthy said MRI exams have shown nothing seriously wrong with the shoulder, but that it simply is not bouncing back as it needs to between starts.

  • Coco Crisp was the symbol of the A's frustration in the sixth inning. Displeased with being called out on strikes by home-plate umpire Tony Randazzo, Crisp was ejected after the inning while still jawing toward Randazzo from the dugout.

    n The A's placed outfielder Collin Cowgill on the 15-day disabled list because of a sprained left ankle. Hicks took his roster spot.

    Cowgill was on crutches before the game, but Melvin said he didn't expect Cowgill to be out for an extended period.

    For more on the A's, go to Joe Stiglich's blog at ibabuzz.com/athletics and follow him at twitter.com/joestiglich.