The Royals optioned Avila to Triple-A Omaha on Thursday.
Avila surrendered five earned runs in just three innings during his season debut against the Brewers on Saturday. He found more success after moving to the bullpen for his next outing, giving up just one run in three frames against Cleveland on Wednesday, but the Royals will remove him from their active roster nonetheless. Mitch Spence will come up from Omaha in a corresponding move to fill Kansas City's need for a multi-inning reliever.