West Ham assistant manager Kevin Nolan was spotted furiously confronting Brentford star Neal Maupay at half-time at the London Stadium.
Maupay was approached by Nolan as the teams emerged for the second half, with West Ham leading 2-1 in the Monday evening Premier League fixture.
According to Sky Sports commentator Gary Neville, Nolan had reportedly been outside referee Simon Hooper's room at half-time.
Nolan was reportedly angered by Maupay, with the dispute continuing down the down.
'There was quite a bit going on at half time as the players came back out from the tunnel,' Neville said.