The French midfielder has highlighted a potential weakness in his former Arsenal team-mate's game as the duo prepare to lock horns in the Champions League on Tuesday
Flamini, who played alongside Fabregas during his Arsenal career, was full of praise for the Spain star's abilities, but has hinted at a possible weakness in the 25-year-old which the Rossoneri could look to exploit on Wednesday.
“Fabregas is a player with many qualities, as he has incredible vision and is also very good in front of goal," he told Milan Channel. "As for his defects, at times he ‘forgets’ to defend."
Barcelona head into the tie as clear favourites to progress, and Flamini conceded he would rather have faced different opponents at this stage in the tournament.
"Barcelona have great individual talents and play wonderful football, so they are among the favourites for the trophy," he continued.
“Admittedly, we would’ve preferred to face a different team at this stage, but they will certainly be two fantastic games.
“We will do everything possible to surprise Barcelona.”