Continuity mistake: The day after the fight in Tijuana, when Donnie's at his desk he's wearing a grey striped tie, but when Donnie walks into his boss' office he's wearing a navy tie with dots. (00:07:30)
Continuity mistake: When Donnie goes down during his fight with Conlan, his position on the mat changes between the closeups and the long shot. (01:57:10)