Harvey will try to lead the Mets to a fourth straight win, and New York catches a break by not having to face the red-hot Hamels on Wednesday night at Citizens Bank Park.
New York (60-69) has won three in a row for the first time since a four-game run June 27-30. The current surge, which includes Tuesday's 9-5, 10-inning victory over Philadelphia (61-68), has been a welcome change for a team that previously endured a 4-14 slump.
Shoppach helped keep the Mets rolling in the opener of this three-game series, hitting a tying double in the eighth and a two-run homer in the 10th after Ike Davis' RBI double gave them the lead for good.
Shoppach was 4 for 17 with one homer and seven strikeouts in his first six games with New York after being acquired from Boston two weeks ago.
It's uncertain if Shoppach will be behind the plate again, but Harvey (2-3, 2.75 ERA) is slated to take the mound as New York goes for an eighth win in nine tries in Philadelphia.
The right-hander has posted a 1.32 ERA over his last two starts, going 1-0 with 17 strikeouts and three walks in 13 2-3 innings. He's struck out 43 in 36 innings since being called up, the most through six games in team history.
Harvey - who's gone 5 for 11 at the plate - struck out nine while allowing one run and three hits in six innings against Colorado last Wednesday.
"Extremely impressed with the way he handled himself, pitching out of trouble, electric stuff again," manager Terry Collins said. "He asks all the right questions. He pays attention. He's the first guy on the bench before the game starts. He's there throughout the game. He listens. He wants to learn.
"He truly is living up to that, 'I'm not here to be one of the guys. I'm here to be THE guy.' And we think we've got some more coming."
The Phillies have won each of Hamels' last four starts while he posted a 1.71 ERA, but the 14-game winner won't get a chance to equal his career high for victories Wednesday. Instead, Tyler Cloyd will be called up from Triple-A Lehigh Valley to make his major league debut.
Cloyd, a 25-year-old right-hander, was 15-1 with a 2.26 ERA in the minors this season, including 12-1 with a 2.35 ERA at Triple-A.
Ryan Howard had a grand slam Tuesday, and he's batted .303 with four homers and 13 RBIs in his last eight games against the Mets.