Manchester United coach Darren Fletcher could reportedly be facing a charge from the FA after he berated match officials at half-time in the Old Trafford tunnel.
Referee Samuel Barrott had ordered United defender Matthijs de Ligt to leave the pitch in first-half added time to receive treatment for a persistent head wound.
Brentford's Ethan Pinnock managed to score from a corner while De Ligt was off the field receiving treatment, leading to United's outrage at being a man down and conceding due to Barrott's decision.
United manager Erik ten Hag and his assistant Ruud van Nistelrooy were both given yellow cards for their heated protests, with Fletcher continuing to express his anger as the teams left the pitch at half-time.
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