CLEVELAND -- Andrés Muñoz, who led American League relievers in strikeouts last season, was put on the 15-day injured list by the Seattle Mariners on Sunday because of a right deltoid strain.
Muñoz struck out 96 while going 2-5 with four saves and a 2.49 ERA in 64 appearances last year. He had ankle surgery in November, which delayed his first spring training appearance until March 20.
He hasn't allowed a run in 3⅓ innings this season with three strikeouts.
Manager Scott Servais said Muñoz has felt soreness in the back of his shoulder.
"He didn't have his normal buildup in spring training," Servais said. "He just hasn't felt great. We're playing the long game here. For us to be really good throughout the course of the season, we need him. The decision was made to give him a couple weeks downtime now and let him get back to what he's used to being."
Right-hander Matt Festa was optioned to Triple-A Tacoma with a 10.80 ERA over three appearances in which he allowed four runs in 3⅓ innings.
Right-handers Justin Topa and J.B. Bukauskas were recalled from Tacoma. Infielder Evan White was recalled from Tacoma and placed on the 60-day injured list with a left adductor strain. He was injured during Tacoma's second game of the season April 1.