PHOENIX -- The Cleveland Guardians called up catching prospect Bo Naylor and put right-handed pitcher Triston McKenzie on the 15-day injured list on Saturday.

The roster moves come one day after the Guardians designated veteran catcher Mike Zunino for assignment.

Naylor, 23, was hitting .254 with 13 homers and 48 RBIs at Triple-A Columbus. The Canadian was selected with the 29th overall pick of the 2018 draft. He'll join his older brother Josh Naylor, who also plays for the Guardians.

McKenzie's elbow issue is the latest injury setback for the right-hander, who missed the first two months with a shoulder strain. The Guardians have high hopes for the hard-throwing McKenzie, who went 11-11 with a 2.96 ERA in 30 starts last season.

McKenzie was brilliant in his season debut June 4, striking out 10 over five scoreless innings. He struggled in his second outing against the Astros last week and was scratched from his planned start against the Diamondbacks on Friday.

Manager Terry Francona said McKenzie had an MRI on Friday night and there was some inflammation, but his long-term prognosis was unclear.

"We just need to let the doctors do their thing," Francona said. "That'll give us a much better idea on a timeline."

Bo Naylor has made two cameos with the Guardians over the past two seasons and has 10 big league at-bats. This time, Francona said he hopes the young slugger is here to stay.

"Nobody has a crystal ball, but that's the idea," Francona said.

Francona said he doesn't know how he'll split the catching duties between Naylor and Cam Gallagher, other than that Naylor will start Sunday's game. The veteran manager added that bringing up a catcher from the minors is sometimes more difficult because of all of the position's responsibilities, particularly handling the pitching staff.

"The game for young catchers can be going so fast," Francona said. "So we'll try to simplify for him."

Zunino was hitting .177 with three home runs, 11 RBIs and 61 strikeouts. The veteran signed a one-year, $6 million deal during the offseason.