To make room on the 40-man roster, right-hander Ryan Dull was designated for assignment.
Valera, 27, has appeared in 12 games with the Yankees this season, hitting .219/.324/.313 with three RBIs and five strikeouts. He began the season in the San Francisco Giants organization. In 107 triple-A games with the Giants’ and Yankees’ minor-league teams, he hit .303/.389/.480 with 14 home runs.
Dull, 29, was claimed off waivers from the Yankees on Thursday and did not appear in a game for the Blue Jays.
The Jays open a three-game series against the Yankees in New York on Friday.