Arsenal ace Robin van Persie sparked a brawl with Benfica players during the weekend's friendly.
The Sun says Van Persie was furious following a crushing challenge from Ezequiel Garay in the 40th minute and unleashed a verbal rocket at the Benfica star on the half-time whistle.
Garay then shoved Van Persie before the pair clashed in front of their amazed team-mates, who ran to join in.
After being dragged away from his opponents Van Persie then headed towards the tunnel before having a verbal spat with Enzo Perez, who tried to lay into the Emirates star.
Both sets of players then piled down the tunnel and it seemed certain that the problems would continue outside the dressing rooms.
Van Persie had needed treatment after going down in the nasty looking challenge. He did not re-appear for the second half.
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