Manager Joe Maddon said Canning was unable to throw Saturday and is likely to begin the season on the injured list, Bill Shaikin of the Los Angeles Times reports.
The 23-year-old was scheduled to throw Saturday as part of his medical tests after an MRI revealed some issues with the UCL in his right elbow, but the elbow apparently didn't feel well enough for him to throw. Canning is now set to undergo further testing to see if it's a joint issue rather than a ligament. The right-hander remains without a timetable for his return, though any time on the injured list would sideline him for at least the first couple series of the season.