"This will give him two days off," Yost said. "Could he have started tonight? Yeah. In fact, he fought me about it. But it's better to take the two days off and be ready for Boston on Friday. He'll be back then."
Perez has been dealing with a strain on his left side for several weeks, but this injury is on the other side. Both injuries occurred while swinging the bat.
"It's nothing major at all," Yost said.
The Royals did bring in Triple-A Omaha catcher Cam Gallagher early Wednesday morning to be on the taxi squad just in case Perez's injury didn't improve.
"But Sal is feeling much, much better," Yost said.