Celtic earned their fourth trophy under Brendan Rodgers on Sunday afternoon.
The Hoops earned a fourth trophy under the stewardship of Rodgers thanks to a 2-0 win over Craigan's old side at Hampden Park, which saw James Forrest and Moussa Dembele score the goals.
Outspoken pundit Craigan applauded Rodgers for the work he has done to keep Celtic's squad focused, but criticised 28-year-old Scott Sinclair as the former Manchester City winger won a penalty in the second half.
It saw Dembele score Celtic's second, as well as giving the Hoops a numerical advantage as Cedric Kipre was sent off. Craigan believes Sinclair was guilty of diving but still commended the Scottish champions for their win.
"The relentless form of his players has been incredible, and they deserve a lot of credit for the style of football they are playing too," Craigan said.
"The toughest part of management is to continually motivate players and get the best out of them, so Brendan deserves all the accolades coming his way.
"Football is a contact sport and players have a professional responsibility towards each other not to exaggerate the contact in order to gain an advantage. I feel Sinclair was guilty of this to win his penalty."
Sinclair earned a penalty with the scoreline at 1-0, ghosting past Kipre only for the 20-year-old defender to have pulled him back. Replays showed that contact was minimal on the winger.
Celtic are now 65 matches unbeaten in domestic football north of the border and will be looking to increase that tally on Wednesday night, as they travel to Fir Park to go up against the likes of Louis Moult, Ryan Bowman and Chris Cadden for a second time in four days.