PEORIA, Ariz. -- Seattle Mariners top prospect Jarred Kelenic will be sidelined due to a strained adductor muscle in his left knee.

Mariners general manager Jerry Dipoto said an MRI on Saturday revealed the injury. No timeline was given for the outfielder's return.

"While disappointed that Jarred will be sidelined, we are relieved that the long-term outlook is positive," Dipoto said. "We all look forward to seeing him back on the field in the near future."

Kelenic appeared to be injured during his first at-bat on Friday against the Chicago White Sox. Kelenic reached on an error, but appeared bothered after reaching first base. Kelenic remained in the game and was replaced an inning later.

The 21-year-old Kelenic, who hit Seattle's first home run of spring training earlier this week against the Cubs, has been the center of attention during spring training.

Kelenic's arrival in the majors was part of comments made by former team president and CEO Kevin Mather that indicated Seattle was considering manipulating Kelenic's service time.

Kelenic and his agent lashed out at the Mariners in comments made to USA Today following Mather's resignation last month. After homering earlier this week Kelenic said he's using those words as motivation.

"I'm a competitor," Kelenic said. "I'm a very driven person as it is. Having said that, you know, something like this comes up, and I think you can look at it one of two ways: One, you can sit and pout about it, or you can use it as motivation and let it drive me even more. That's kind of where I'm at. Each and every day I'm letting this drive me."