"I feel pretty good." Perez said. "I don't feel anything -- any pain, anything."
Perez also caught a side session in the bullpen and continued to throw, with manager Ned Yost saying if the Royals needed to activate Perez when he's eligible on Tuesday, he could get behind the plate without issue.
"All of his catching stuff has been totally asymptomatic," Yost said. "He isn't feeling anything right now."
"The worst part of it is hitting," Perez said. "So we're just going to wait and see how my muscle is going to respond to hitting."
Perez is batting .278 with 21 homers and 65 RBIs. The Royals have gone 3-6 without Perez, leading Yost to quip, "It seems like it's been a year since he got hurt." But the progress Perez has made makes Yost confident they'll get him back soon.
"We said that four weeks would be worst-case scenario, so he's making really good progress," Yost said. "We'll just see. I'm not really putting a timetable on it. We want to get him back as soon as we can, that's pretty obvious. But we want to make sure he's healthy when we do."
Yost also mentioned that, while a decision isn't final, he thinks Perez may not need a rehab assignment.
"If he's able to play, we probably want him to play up here," Yost said.
Worth noting • The Royals optioned right-hander Kevin McCarthy to Triple-A Omaha on Monday. Kansas City needed a roster spot for Jake Junis, who started against the A's.
After being called up when Trevor Cahill went on the DL Thursday, McCarthy pitched three times, with the only blemish coming when he allowed three unearned runs to the White Sox on Sunday.