Gestede came off the bench to score in the 77th minute and reduce the visitors' lead to 2-1 before Antonio Valencia's late goal wrapped it up for United.
In between the two goals there was a scuffle between both sets of players, prompted by a coming-together between Gestede and Bailly, and mixed reports claimed that one of the two had bitten the other.
It was also reported that a bust-up between both sets of players occurred at the end of the match in the tunnel, with security apparently having to step in.
Gestede addressed the biting reports, telling Sky Sports News: "We had a few words together, it was nothing major. He gave me a hug and a kiss, that's it. I didn't feel anything.
"Ben [Gibson] thought he bit me, so that's why he reacted like he did. But I told him now we were just talking, there was no problem."
Both clubs could now face disciplinary action from the Football Association depending on referee Jon Moss's take on proceedings at the end of the league fixture.