He was removed for a pinch-hitter in the bottom of the seventh because he has been complaining of tenderness in his pitching shoulder before each of his past three starts.
Any pain felt by Peavy is a pain all of the Padres feel.
He will skip his in-between-starts bullpen session this week, although he is scheduled to start Sunday against the Cardinals.
How concerned are the Padres about Peavy's pain?
"It's not unusual to get that occasional tendinitis," said Padres manager Bruce Bochy. "Once he gets loose, he's fine. We think we have it under control. The trainers feel he will be OK. But no way was I going to risk it (Tuesday). I'm not going to risk losing this kid."
Said Peavy: "I don't think it's a concern for me not being able to pitch. Anytime you feel discomfort, it's not good. We're going to continue to get treatment on it and work through it. We've just got to continue maintaining it and staying on top it."
But Peavy is not the only health concern.
Right-hander Woody Williams could be on the disabled list with a strained calf muscle until September.
And the Padres have pushed the return of left-hander Shawn Estes back from mid-June to an undisclosed time. Estes has been on the disabled list since his first start with a strained flexor tendon in his elbow. He felt pain in the elbow after a bullpen session Sunday, and an MRI Tuesday showed increased looseness in the ulnar collateral ligament. He is also going to get a second opinion.