Victorino is suffering from a strained right hamstring. He won't be eligible for activation until June 3 at the earliest.
The Phillies said an MRI exam on Thursday revealed something between a Grade 1 and 2 strain. The team will announce Victorino's replacement Friday, although general manager Ruben Amaro Jr. said it will not be Triple-A Lehigh Valley outfielder Domonic Brown.
"We don't think he's ready to do it," Amaro said about Brown.
Scheduled to start, Blanton was replaced right before game time on Thursday by Kyle Kendrick when he threw about 20 pitches in the bullpen and decided he could not continue.
"I probably rushed myself back too quick," Blanton said.
Lehigh Valley right-hander Vance Worley likely will replace Blanton in the rotation.
Blanton had been on the disabled list earlier this month because of a medial impingement in his right elbow. He rejoined the rotation May 9 in Florida, but he still experienced soreness in his two starts since rejoining the team.
Blanton expects to have another MRI on Friday. An MRI exam earlier this season revealed no structural damage, which is why Blanton said he felt comfortable trying to pitch through the soreness he felt in the elbow.
"Every pitcher has things that don't feel good," Blanton said. "They said structurally I was fine. I didn't feel bad when I first came back. I thought I'd be able to manage it from start to start until it got better. It just kept getting worse."