Manchester United duo Bruno Fernandes and Lisandro Martinez reportedly led an inquest at half time of Sunday's 6-3 defeat to rivals Manchester City.
The Red Devils entered the derby meeting off the back of four consecutive Premier League victories, but any hopes of a victory over their neighbours had dissipated by the interval.
Erling Braut Haaland and Phil Foden netted two goals apiece to help Man City surge into a 4-0 lead that resulted in a furious reaction from Fernandes and Martinez at half time.
According to The Mirror, the pair accused their teammates of lacking belief, while their angry outburst was reportedly heard by members of the Man City backroom staff, who were situated outside the home dressing room.
Erik ten Hag was believed to be accepting of the exchange, with the United boss happy for the players to have their say.
Although United managed to score three goals in the second half, Haaland and Foden both wrapped up their respective hat-tricks to condemn their rivals to a 6-3 defeat.
United will have the chance to bounce back on Thursday when they face Omonia Nicosia in the Europa League before they travel to Goodison Park for Sunday's Premier League meeting with Everton.
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