SAN FRANCISCO -- Omar Vizquel's double in the 13th inning helped the Giants defeat the Nationals, 4-3, in front of 36,903 fans at SBC Park on Sunday afternoon.

With none out and reliever Jon Rauch on the mound, Jason Ellison started the inning off by getting an infield single. After Ellison went to second on a wild pitch, Vizquel followed and hit a liner to right fielder Jose Guillen. The ball looked like it was going straight to Guillen in shallow right, but the ball went over his head for the game-winning double. The winner was Jason Christiansen.

"I was playing in a little bit thinking that Vizquel was going to bunt. He hit the line drive. The ball took off and it went over my head," Guillen said.

The run spoiled a great outing for Rauch, who pitched three innings and gave up the one run.

"I gave it up. I'm in there to keep the ballgame close and kind of let the team down. I should have made the pitch to allow Vizquel to bunt," Rauch said.

The game seesawed back and fourth and had its share of controversy. The Nationals gave starter Esteban Loaiza the lead in the first inning, when Guillen hit his eighth home run of the season off left-hander Kirk Rueter.

The Giants tied the score in the third inning, when Vizquel grounded out to first base to score Deivi Cruz.

The Nationals untied the score when Guillen drove in Loaiza with a sacrifice fly in the fifth inning.

The Giants then scored their second run of the game on a controversial play in the bottom of the inning. With Yorvit Torrealba on third base, Vizquel hit a ground ball at deep short. It looked like shortstop Cristian Guzman threw out Vizquel, but first-base umpire Greg Gibson called Vizquel safe. The replay appeared to show that Vizquel was out.

"It was a close call. Obviously, I thought he was out, but he called him safe and you can't change it," said second baseman Jamey Carroll, who went 4-for-6. "But we had opportunities and the Giants made the pitches at the right time."

With two out in the top of the seventh, the Nationals made it a 3-2 game. With Carroll at first base, Guillen took a Rueter pitch and hit a routine fly ball to center fielder Michael Tucker. But the wind gave Tucker problems as the ball kept carrying. Tucker then went left as the ball hit his glove and dropped in for a two-base error. Carroll scored all the way from first base on the play.

The Giants scored another controversial run in the bottom of the eighth inning. With Vizquel at first, Edgardo Alfonzo hit the ball down the left-field line. A fan touched the ball, but home-plate umpire Lance Barksdale allowed Vizquel to score. Manager Frank Robinson argued the play to no avail.

The Nationals believe that Vizquel wasn't even close to third base and it wasn't a guarantee that he was going to score.

"To me, it wasn't obvious, because I was going to cut the ball off before it reached the wall," said left fielder Brad Wilkerson. "If it was going to get to the wall, then you could make that call. But you can't assume that he's going to score."

Crew chief Charlie Reliford said it's not automatic that runners should have been placed on second and third.

"It's not automatically anything," Reliford said. "What happens after spectator interference is the umpires place the runner at the base that they would have reached, in the umpires' judgment, had the interference not occurred.

"So even if he's well short of third base when the interference happens, you call it that way. You look at the play and say, 'This is what we think would've happened had the spectator not touched the ball.' In fact, one of the most common things you hear on TV is ground-rule double, and that's the thing. It's not."

Robinson felt that the call cost the Nationals the game.

"You go out there on the field and you compete and if you get beat, you get beat. ... But you don't like it when they take it away from you," Robinson said.

Loaiza did not figure in the decision. He pitched 7 2/3 innings and gave up three runs on nine hits.

"I had to stretch him today because of the bullpen. I probably had him out there one inning too long," Robinson said.