The Phillies tied it in the ninth with an unearned run, scored twice in the 10th with two extra-base hits and survived in the bottom half of the inning to win their second straight.
With runners on second and third and two out in the Atlanta 10th, Yunel Escobar singled to center off closer Brad Lidge. Josh Anderson scored from third, but Victorino gunned down Blanco with a perfect throw.
Victorino also tripled in the go-ahead run in the top of the 10th and scored on a double by Chase Utley.
Philadelphia tied it at 2-2 in the ninth when, with two out and pinch-runner Eric Bruntlett on second, a grounder by Chris Coste was booted by second baseman Kelly Johnson. Bruntlett raced around to score.
Tom Gordon (5-2) got the win by pitching the ninth and Lidge picked up his 16th save.
The loss went to Manny Acosta (3-4), who was charged with Philadelphia's two 10th-inning runs.
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