Joey Barton, manager of English Championship side, Fleetwood, reportedly headbutted and punched rival manager, Daniel Stendel, after his team’s 4-2 defeat on Saturday.
Barton is said to have confronted Stendel, Barnsley’s coach, in the tunnel when the game ended in favour of the home team.
According to The Sun, Police said they are investigating the incident involving the controversial coach.
The report added that Barton grabbed Stendel on the throat, during which he lost two teeth.
Barnsley striker, Cauley Woodrow, was said to have also tweeted that Barton confronted Stendel following the game, although he later deleted the it.
Woodrow, who scored in his side’s victory, claimed Stendel was left with “blood pouring from his face”.
A South Yorkshire Police spokesperson said: “We are aware of something that has taken place in the tunnel after the game and we are investigating.”
The report added that neither club attended their post-match media duties.
Barnsley said in a statement: “The club can confirm there was an alleged incident in the tunnel area that took place following the conclusion of today’s match, which South Yorkshire police are currently investigating.
“The club is assisting the police with its enquiries and, as a result, we are not in a position to make any further comment at this time.”
A footage tweeted by Sky Sports News showed Barton being stopped by police while leaving the stadium’s car park.
Shaun Harvey, EFL Chief executive, has promised the body will help investigate the alleged incident.
“As an off-the-field matter the tunnel is still in the domain of the referee but we will work closely with everybody to ensure it’s not a case of who deals with the matter but actually the matter is dealt with properly, Harvey told BBC Radio 5 Live.
“The police investigation is ongoing so we need to leave the details for them to deal with.”