West Bromwich Albion's Jayson Molumby punched an opponent in the face during a pre-season friendly against Mallorca.
The closed-doors match descended into chaos towards the end of the first half, when a spat erupted between Molumby and Mallorca's Samu Costa.
In a video on Reddit, Molumby can be seen carrying the ball before being challenged twice, the second time being a foul by Costa.
As the pair come together words are angrily exchanged, but the row turns to violence with the flashpoint of Molumby sticking his forehead into Costa's face.
Costa retaliates by placing a hand on Molumby's neck, but the 24-year-old Irishman shockingly decides to make a closed fist, and punch Costa in the face.
Baggies midfielder Jayson Molumby (front) swings a punch at an opponent during a friendly
The moment Molumby (front) connects with a punch to Mallorca's Costa's (rear) face
The pair then tussle to the floor, as teammates rush over to break-up the fight.
As it was a friendly game, no red card was shown to either player by the referee, but Molumby was substituted at half time.
It remains to be seen if any disciplinary action will taken by the club, but the scenes were shocking for the level of violence on display, from seemingly out of nowhere.
Molumby began his career at Brighton as a member of their academy, before making five senior appearances for the Seagulls.
He spent the 2019-20 season on loan at Millwall, and then the second-half of the 2020-21 campaign at Preston.
West Brom and Mallorca players attempt to separate the pair as they fall to the ground fighting
Since then, Molumby has made 103 appearances for the Baggies, registering five goals and five assists in all competitions.
West Brom's went on to lose the friendly 1-0 against Albion, following a second-half strike from David Lopez.
They've now lost twice in pre-season, to Bolton and Blackpool, and have won just once against Peterborough, as they prepare for next season in the Championship.