KANSAS CITY, Mo. (TNS) — The Royals officially placed catcher Salvador Perez on the 10-day disabled list Sunday. Now the wait continues as the club seeks to determine how long its All-Star catcher might be out.

Perez was expected to go on the disabled list after sustaining a strained intercostal muscle in his right side Friday night in a loss against Seattle. He was replaced on the 25-man roster by catcher Cam Gallagher, a 24-year-old batting .294 at Class AAA Omaha.

The Royals still do not have a time line for how long Perez might be sidelined. Royals manager Ned Yost said Saturday that Perez could miss anywhere from 10 days to four weeks. For now, Yost remains hopeful that Perez can return in close to two weeks.

"You got to look at it in terms of reality," Yost cautioned. "But I don't think it's going to be ... when I said four weeks, that was absolute worst-case scenario. Do I think it's probably going to be a lot less than that? I do."

Perez will be reevaluated on Monday or Tuesday, Yost said. The club could have a better idea on the severity of the strain and the recovery process after additional tests.

"These things get swollen and full of fluid and you have to give it some time to get out of there, so you can really take a good look at the extent of the injury," Yost said.

Gallagher, the Royals' second-round pick in 2011, will make his major league debut when he makes his first appearance. A native of Manheim Township near Lancaster, Pa., Gallagher posted a .339 on-base percentage with five homers at Omaha. He spent all of the 2016 season at Class AA Northwest Arkansas, batting .259 with a .348 on-base percentage.