London - Third tier English side Barnsley issued a formal complaint to the Football League and the Football Association on Tuesday over Fleetwood Town manager Joey Barton's alleged assault on his counterpart Daniel Stendel.
Barton is reported to have confronted Stendel in the tunnel following Barnsley's 4-2 victory last Saturday that all but ended Fleetwood's hopes of reaching the play-offs in what is Barton's first season in charge.
Barnsley player Cauley Woodrow tweeted in the immediate aftermath that Barnsley's German manager had been "physically assaulted" and left with "blood pouring from his face".
Woodrow later deleted the tweet.
Barton was captured on TV being prevented by a police officer from leaving the stadium car park. Barnsley said they were helping police but had also decided to go to the football authorities.
"Barnsley Football Club can confirm that it has lodged a formal complaint to both the English Football League and the Football Association," said a club statement.
"This is following an alleged incident at the conclusion of the match on Saturday 13th April, between Joey Barton and Daniel Stendel.
"The club is also currently working with the police and assisting with all enquiries regarding the incident. No further comment will be issued whilst police investigations are ongoing."
Barton was a surprise choice when Fleetwood appointed him last year in what was his first foray into management.
Barton, 36, was a talented but volatile player who was embroiled in a few scraps, on and off the pitch, during his playing days.
He won one England cap during a career that saw him play for a host of clubs including Manchester City and Marseille. His playing career ended at Burnley.
Barton's chequered career has seen him banned for 18 months after he was investigated for placing 1,260 bets on football matches between 2006 and 2016.
In May 2008, he was jailed for six months over a late-night attack on a man and a teenage boy in the centre of his home city of Liverpool.
In July that year he was given a four-month suspended jail term for attacking his Manchester City team-mate, Ousmane Dabo, in training.