WASHINGTON (AP) -- Buster Posey hit a tiebreaking single in a four-run seventh inning and added a two-run homer that withstood a video review in the San Francisco Giants' 10-5 victory over the Washington Nationals 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 full-count 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.
Juan Uribe then hit a two-run double to right-center for an 8-5 lead.
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.
Posey finished with four hits and three RBIs.
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 finished with 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.