Trash talking boxer Adrien Broner got his ass beat and his welterweight title stripped in a stunning loss to Marcos Maidana this Saturday … but TMZ Sports has learned, there’s now a full-blown investigation into allegations of cheating.
Sources close to “the Problem” tell us … the Texas Boxing Commission is now analyzing video of the fight which some say shows Maidana taking what looks like a pill during the WBA welterweight championship fight last Saturday.
The rules are so strict … even water needs to be tested prior to a fight before the boxer can consume it. Pills and any other substance for that matter are off limits.
Broner — who was previously undefeated — says the loss hasn’t shattered his ego … he’s confident the investigation will prove Maidana cheated.
We’re told the boxing commission will reveal the results of the investigation in 1-2 days.