KANSAS CITY -- A little less than 72 hours after Royals All-Star catcher Salvador Perez sustained a right intercostal strain, Perez had no more insight into how long he would remain on the disabled list.
The intercostal is a group of muscles located between the ribs that work to stabilize the chest wall.
"We don't have a timetable right now," Perez said before Monday's game against the Cardinals. "We don't have one exact day to come back. It will at least have to be 10 days. Hopefully it will just be 10 days."
For now, Perez will continue to receive daily treatment, including the anti-inflammatory injections he received on Sunday.
"It feels better today," Perez said. "Yesterday was a little painful. Today's pain went down a little. I think the injections are starting to work."
The Royals' medical staff is waiting for the inflammation in Perez's right side to subside before making a more definitive estimate on his recovery time.
Meanwhile, Perez is trying to cope with being on the disabled list for the first time since 2013.
"It's terrible," Perez said. "I don't like it. But it's part of the game. I feel a little sad when I see my teammates play and I can't help."
Perez has been dealing with nagging issues on both sides of his torso since May. But the strains were not severe enough then to keep him out of the lineup.
"It started in May," Perez said. "I felt something there. Something sore, something tight. But it was something I could control.
"I don't think a little rest would have helped. They told me if I wanted it to go away, I should sit and let it heal for a month.
"We're fighting for another chance at a playoff. It's hard. I want to play."
But on Friday night against the Mariners, Perez swung hard and missed at a 2-0 pitch in the dirt. And the pain was indeed more evident than earlier this season.
"It only hurts when I swing and miss," Perez said. "I was feeling something, a little pinch on left side and right side. I felt it worse that night. It was a 2-0 count. Swung and missed. Then it hurt."
Perez came out of the game immediately and later on Friday night, he got the bad news after getting an MRI.
"All I can do is work hard and get treatment," Perez said. "The harder I work the faster I'll come back."
Jeffrey Flanagan has covered the Royals since 1991, and for MLB.com since 2015. Follow him on Twitter @FlannyMLB. This story was not subject to the approval of Major League Baseball or its clubs.