Toronto signed 49-year-old left-hander Jamie Moyer to a minor league contract, according to a report on the team's website late Monday.
The veteran pitcher will report to the team's triple-A club in Las Vegas, where he will attempt to crack the Jays' roster.
Reports of the move surfaced after Toronto's 9-6 victory in Boston, where Jays starter Henderson Alvarez pitched five innings then left with right elbow soreness.
Toronto's rotation has been hit hard by injuries recently. Starters Brandon Morrow, Kyle Drabek and Drew Hutchison were all placed on the 15-day disabled list.
Moyer, meanwhile, started the season with Colorado, where he became the oldest pitcher to win a game in the big leagues. He went 2-5 before being designated for assignment by the Rockies on May 30.
He subsequently signed a minor-league contract with Baltimore on June 6. After three starts at triple-A Norfolk, he requested to be released and opted for free agency.
Moyer has spent parts of 25 seasons in the majors. His lifetime record is 269-209.