Giants 4, Nationals 2 (10): Pablo Sandoval blasted a two-run homer off Yunesky Maya in the 10th inning and host San Francisco rallied for its second straight win over Washington after Gregor Blanco tied the game with a two-out RBI triple in the ninth.

Marco Scutaro singled with one out before Sandoval crushed a 1-0 pitch from Maya (0-1) into the right-center field seats for his second career walk-off home run. Jeremy Affeldt (1-0) worked a scoreless 10th inning for the win.

Washington lost its fourth straight game after Rafael Soriano recorded his second straight blown save in the ninth. Buster Posey led off the ninth with a single and was replaced by pinch runner Andres Torres, who scored on Blanco’s triple.

The late-inning drama overshadowed a quality pitchers’ duel between the Nationals’ Stephen Strasburg and the Giants’ Matt Cain. Strasburg allowed one run with seven strikeouts while throwing 108 pitches over seven innings, and Cain allowed two runs while striking out seven over seven frames.

Washington did all its scoring in the first when Ryan Zimmerman and Ian Desmond each doubled in runs. San Francisco scored in the fourth when Blanco hit a leadoff single and scored on Angel Pagan’s two-out single.

GAME NOTEBOOK: The Giants placed RHP Ryan Vogelsong (hand) and RHP Santiago Casilla on the disabled list and recalled 1B Brett Pill and RHP Sandy Rosario from Triple-A Fresno. … Scutaro went 2-for-4 and extended his hitting streak to 19 games, the longest in the majors this season. ... The Nationals placed RHP Ryan Mattheus (hand) on the disabled list and recalled Maya and LHP Fernando Abad from Triple-A Syracuse.