The Mets recorded back-to-back shutouts on Sunday and Tuesday and Matt Ginter did not allow a run in six innings on Wednesday to give New York a 28-inning scoreless streak.
It was their longest in 14 years.
But things fell apart in the seventh with a help of two errors that quickly erased a 3-0 lead.
David Bell greeted reliever Ricky Bottalico with a ground ball that shortstop Kaz Matsui booted. Mike Lieberthal delivered the first Philadelphia run with a double and pinch-hitter Jason Michaels walked one out later.
John Franco (0-3) relieved and gave up a run-scoring single by Doug Glanville. Chase Utley followed with a grounder to first base.
Mike Piazza, who is attempting to make the transition from catcher to first base this season, fielded the ball cleanly and looked for the force at second. But his throw sailed over the head of Matsui to bring home the game-tying run.