Giants 10, Nationals 5

Buster Posey showed the Washington Nationals what it's like to be beaten by a rookie.

A night after Nationals phenom Stephen Strasburg shut down the Giants, Posey hit a tiebreaking single in a four-run seventh inning and added a two-run homer that withstood a video review to lead San Francisco to a 10-5 victory over Washington on Saturday night.

Brought in to protect a 5-4 lead in the seventh, Tyler Clippard (8-6) allowed Aaron Rowand's one-out homer to left on a 3-2 changeup. Freddy Sanchez and Aubrey Huff walked, and both were running when Posey sent a single through the hole between first and second to put the Giants ahead.

''Full count, I was just battling,'' said Posey, who had his second career four-hit game in four nights. ''I knew from watching some previous at-bats, (Clippard) had a lot of confidence in his changeup, and I knew if I was going to get beat, I didn't want to get beat with the changeup.''

Juan Uribe then hit a two-run double to right-center for an 8-5 lead.

Clippard has been a dependable setup man, and leads the Nationals' pitching staff in victories, but is 0-3 with 11 runs allowed in his last 6 1-3 innings over seven appearances.

''Tyler's just struggling. ... He's gotten hurt a little bit with his changeup,'' Washington manager Jim Riggleman said. ''He's got a great changeup, but word gets around the league a little bit and every now and then maybe a hitter's looking for it.''

In the ninth, Posey hit a drive to right-center off Miguel Batista that was bobbled and caught by a fan in the first row wearing a Giants cap. The fan appeared to reach over the railing, but the umpires used a three-minute review to uphold the call.

''It wasn't a great feeling,'' Posey said of the brief stoppage. ''I really didn't want to go out there to second base, so I was glad it held up.''

It was Posey's seventh homer since being recalled from Triple-A Fresno on May 29 - and his sixth in 10 days. In July, the 23-year-old is hitting .514 and has 13 RBIs.

''I try not to have too many expectations,'' he said. ''I try to set myself a goal, whether it's for a year or a week or a day - just go out and play as hard as I can and the results take care of themselves.''

From behind the plate, Posey also made two key defensive plays in the sixth to short-circuit a Washington rally. He threw out pinch-runner Roger Bernadina at third as he tried to advance on Ian Desmond's attempted sacrifice and later nabbed Desmond trying to steal third.

''Big play. We were in a bit of a jam there and (Posey) made a great throw to third (on the bunt),'' Giants manager Bruce Bochy said. ''He batted well with runners in motion, he found a hole. And at the end, those were big runs to tack on.''

On the one-year anniversary of his no-hitter against San Diego, Giants left-hander Jonathan Sanchez lasted only 3 2-3 innings, yielding five hits and five runs. He walked two and struck out six in his shortest outing of the year.

Santiago Casilla (2-2) got the final two outs of the sixth.

Uribe also had three RBIs for San Francisco, which has won six of eight games.

Sanchez's wildness spotted the Nationals a 2-0 first-inning lead. Justin Maxwell and Cristian Guzman drew walks before an RBI double by Ryan Zimmerman. Sanchez's wild pitch scored Guzman.

Sanchez helped himself out with a two-run single off Craig Stammen that gave the Giants a 3-2 lead in the second. With runners on first and second, Nate Schierholtz doubled into the right-field corner, scoring a run, and Sanchez followed with a single to center.

Michael Morse homered to center leading off the Nationals second.

Washington chased Sanchez in a two-run fourth. John Willingham legged out an infield single and scored on a double to left by Ivan Rodriguez. With two down, Stammen's ground-rule double made it 5-3 and Sanchez was pulled.

Stammen departed in the sixth after Uribe's sacrifice fly got San Francisco to 5-4. The right-hander yielded four runs and six hits.

NOTES: Washington ended a franchise record streak by not allowing a first-inning run for the first time in 10 games. ... Maxwell was recalled from Triple-A Syracuse before the game. ... Uribe (sprained left ring finger) returned to the Giants lineup after missing four games, but OF Andres Torres (left groin tightness) sat out. ... Nationals C Jesus Flores, who has been on the disabled list all season while rehabilitating a right shoulder injury, has been shut down until after the All-Star break because he is experiencing pain, said general manager Mike Rizzo.