Franco homered and drove in four runs and the Phillies held off Milwaukee's ninth-inning rally for a 10-9 victory.
"We didn't tell him he was going to be starting," Philadelphia manager Gabe Kapler said. "He worked great at-bats. He punished pitchers when they made mistakes. (Franco) has shown an incredible attitude recently."
Franco, who had been out of the lineup recently after struggling at the plate, said he comes prepared to play, even when his name isn't on the lineup card.
"I can't control that," Franco said. "I just try to be ready every single day."
"We thought he went deep, the way it looked off the bat," Thames said. "We were close to tying that game."
Tommy Hunter (2-0) picked up the win with one inning of relief.
Hoskins hit a two-run homer in the first off starter Chase Anderson (5-6). Hoskins connected for the second straight day and his 10th of the season.
Thames had his first career leadoff home run, a drive into the right-field bullpen off Aaron Nola. Milwaukee tied it in the third on Lorenzo Cain's RBI double before Philadelphia regained the lead in the fourth on Franco's two-run homer.
Franco is 5 for 10 with three home runs in his career against Anderson.
The Brewers pulled even in the fifth on a run-scoring double by Travis Shaw, who then scored on Aguilar's single that chased Nola.
Nola gave up four runs and seven hits in 4 1/3 innings.
Franco's bases-loaded single in the seventh drove in two more as the Phillies extended the lead to 8-5. Philadelphia added another run in the eighth on Scott Kingery's RBI double.
Herrera hit a leadoff homer in the ninth to grow the lead to 10-5 before the Brewers rallied.
The Brewers optioned RHP Jorge Lopez to Triple-A Colorado Springs and recalled RHP Adrian Houser.
Hernan Perez started at shortstop in place of struggling Orlando Arcia. "He's been swinging the bat pretty well," Brewers manager Craig Counsell said of Perez. Arcia, who is hitting .204, was sent to Triple-A Colorado Springs on May 25 but returned five days later after his replacement, Tyler Saladino, injured his left ankle. Perez had two doubles and a walk in five plate appearances.
NOLA'S STREAK ENDS
Nola failed to pitch at least five innings for the first time since May 31, 2017, snapping a streak that spanned 35 starts. "My command wasn't where it usually is," Nola said. "They hit me around a good bit. They were on me every inning."
Phillies: Williams was hit on the left elbow by a pitch in the fourth but remained in the game.
Brewers: Houser vomited behind the mound while warming up in the eighth. He stayed in the game and faced two batters before vomiting a second time. He again remained on the mound and faced three more hitters to finish the inning.
"I think it was a combination of traveling this morning and not having a lot of food in me. I was trying to stay hydrated in the bullpen. It's pretty hot here compared to Colorado Springs. All combined, it got me."
Houser's willingness to stay in the game impressed Kapler.
"I have a lot of respect for anybody who would step behind the mound and throw up and step back on the mound and pitch," he said. ... LHP Wade Miley, sidelined since May 9 with a left oblique injury, threw a simulated game Sunday morning. He will begin a rehab assignment at Double-A Biloxi. ... Zach Davies, on the DL with right rotator cuff inflammation, is expected to make a rehab start on Tuesday at Triple-A Colorado Springs.
Phillies: Nick Pivetta (4-6) will pitch the opener of a three-game set against St. Louis.
Brewers: Jhoulys Chacin (6-1) takes the mound in the opener of a three-game series at Pittsburgh.
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