Two Feyenoord players became embroiled a in a furious bust-up during a practice session in Portugal.
The Dutch club have taken advantage of their league's winter break by the sending the squad to a winter training camp in Albufeira.
But teammates Miquel Nelom and Tonny Vilhena have risked disciplinary action from the club after a fight broke out during a training drill on Thursday.
The duo were pictured furiously kicking out at each other while fellow players and manager Giovanni van Bronckhorst attempted to diffuse the situation.