Cecil suffered the injury while cleaning a blender in the visitors' clubhouse on Wednesday morning in Boston. It's the second time in two years he cut his throwing hand, as he previously injured himself while cutting chicken during Spring Training 2010.
"[He] came in yesterday, tried to throw some on flat ground and felt through the repetition, as he was going through it, that the cut on the index finger was probably going to open up even more if we continued to go forward or pitch today," Blue Jays manager John Farrell told reporters prior to the series opener against the Yankees on Friday.
Right-hander Dustin McGowan was moved up two days to take Cecil's spot in the rotation. The 29-year-old made the start on normal rest because of the club's recent two off-days.
The decision to start McGowan was a relatively easy one for Farrell to make because he wanted to give rookie right-hander Henderson Alvarez an extended period of rest before his next outing, which will be Saturday.
McGowan, who is coming off rotator cuff surgery on his right shoulder, also doesn't throw off a mound between starts. He was informed of the club's decision on Thursday and is able to make the switch without much difficulty.
"This wasn't like we called him this morning and said 'Hey, you're pitching tonight,'" Farrell said of McGowan, who last pitched on Sept. 11 and allowed four runs in three-plus innings against Baltimore.
"We didn't want to bump Alvarez up sooner. We wanted to be sure we built in some rest for him. We felt like McGowan was an easier adjustment moving him ahead of Alvarez. ... It was the least disruptive to the remainder of the rotation."
Alvarez will start the second game of the series as previous scheduled, and right-hander Brandon Morrow will move up one day to start on Sunday.
Cecil is currently listed as day to day and is expected to miss just one start. He is 4-9 with a 4.37 ERA in 18 outings this year.