The Brewers are looking to get off to a good start against Philadelphia after losing all six match ups last season.
Milwaukee has won eight of its last 10 games overall to move back to the .500 mark.
“There was some opportunities (to score more runs),” Brewers manager Ned Yost said. “We didn’t make anything happen.”
Hardy was batting .147 before his first pinch hit in his second try this season.
“I guess I was the last one on the bench,” Hardy said after Milwaukee’s fourth walk-off win in nine games. “I have been through some tough times lately. It feels pretty good.
Brewers first baseman Lyle Overbay left the game after two innings with a strained right hamstring, but is expected to play on Monday.
“It stiffened up on him,” Yost said. “It’s like a cramp. He was OK. He didn’t want to come out.”
Overbay and the Brewers will try to keep their bats going against Phillies hurler Randy Wolf on Monday.
Wolf has struggled to regain the form that helped him win a career-high 16 games in 2003. The 28-year-old southpaw has lost three straight decisions, including a 3-2 loss to the New York Mets on Wednesday. Wolf gave up three runs and five hits while walking four in seven innings.
Philadelphia has lost six of 10 and is to put wins together.