Cecil arrived at Florida Auto Exchange Stadium feeling under the weather and the club opted to give him the morning off for precautionary reasons.
The 25-year-old went onto the field shortly after noon local time to go through a light throwing program with pitching coach Bruce Walton. The club wanted to ensure he got at least a little bit of work in to keep up with his throwing program.
"He has been dealing with a bit of a migraine," Toronto manager John Farrell said late in the morning. "We held him out of the early work to give him a chance to clear up ... That was the reason he wasn't out there."
Cecil went 4-11 with a 4.73 ERA in 123 2/3 innings for the Blue Jays last season. He dropped 32 pounds during the offseason and will be looking to regain his form from 2010 that saw him lead the team with 15 wins.