Avila is on the Guardians' roster for the ALCS versus the Yankees, Mandy Bell of MLB.com reports.
Avila (0-1) allowed a run on three hits and two walks while striking out four over three innings to take the loss Tuesday versus the Tigers.
The Padres designated Avila for assignment Friday.
Avila improved to 2-2 on the season in Sunday's 10-1 win over the Athletics, tossing three scoreless innings while allowing just one hit and one walk and striking out five.
Avila will start Thursday's game against the Giants at Petco Park.
Avila is scheduled to start Saturday's game against the Brewers at American Family Field, AJ Cassavell of MLB.com reports.
Avila has made his last two appearances for the Padres on Aug. 6 and Aug. 12 as a long reliever, working 9.1 innings between the two outings while striking out nine and giving up one earned run on eight hits and one walk.
Avila will start for the Padres on Tuesday at Colorado, Jeff Sanders of The San Diego Union-Tribune reports.
The Padres recalled Avila from Triple-A El Paso ahead of Sunday's game against the Tigers.
Avila made his first appearance Wednesday for Triple-A El Paso since being optioned to the affiliate July 3, working a scoreless inning in relief while allowing one hit and one walk in an 11-10 extra-inning win over Oklahoma City.