Burnett was forced to leave Friday night's 7-6, 12-inning win over the Boston Red Sox with discomfort in his right elbow.
Burnett, making just his second start of the season after spending the beginning of the year on the DL with the same problem, was charged with three runs on five hits in only four innings. The right-hander struck out five and walked just one, but left the game after throwing 78 pitches.
The pain is similar to what he experienced in spring training, which was the result of scar tissue from elbow surgery earlier in his career.
In the first year of a five-year, $55 million contract, Burnett is scheduled to visit noted surgeon Dr. James Andrews in Birmingham, Alabama sometime in the near future.
Burnett is 0-1 with a 6.30 ERA in two outings this season.
Toronto recalled right-handed pitcher Shaun Marcum from Triple-A Syracuse.