Prior hadn't thrown off mound since March 22
Prior, on the disabled list because of a sore Achilles tendon and tender elbow, threw 10 pitches off the mound before the Cubs' game against the Pittsburgh Pirates. He also threw in the outfield.
"It's just a baby step," Prior said. "The progress is I at least had a release point today where I had an idea where the ball was going. My long toss felt pretty good. My arm strength is getting closer to where I'd like it to be. It feels all right now. I don't expect to wake up any different tomorrow."
The Cubs are hoping to have the 23-year-old right-hander back by early to mid-May. Prior was 18-6 with a 2.43 ERA last year as the Cubs came within five outs of the World Series.
"We're going to take it slow," Prior said. "We're not going to push it."
Prior said Sunday he wasn't ready to throw off a mound, and at the time he was so uncertain of his return that he said he's stopped thinking about a possible timetable.
"I have been told to keep it open-ended, don't set myself up," Prior told the Chicago Sun-Times. "It's frustrating because I want to be out there, but I want to be out there healthy."
Prior was 18-6 with a 2.43 ERA and 245 strikeouts in his first full big league season last year, finishing third in voting for the NL Cy Young Award.
On Tuesday, manager Dusty Baker shot down a Newark (N.J.) Star Ledger report that, citing confiding anonymous "baseball executives," claimed Prior might need Tommy John elbow surgery.
"I guess somebody is trying to start something," Baker was quoted as saying in the Chicago Tribune.
Information from The Associated Press was used in this report.
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