Arne Slot was left raging just one minute into Liverpool's clash with Manchester United after the visitors took a surprise lead early on in the match. Liverpool midfielder Alexis Mac Allister had been involved in a collision with team-mate Virgil van Dijk and was left in a heap on the floor, clutching his head.
The game continued, only for summer signing Mbeumo to be slipped in, with the attacker finishing smartly to put the Red Devils 1-0 up. The home fans inside Anfield, along with the manager himself, directed their frustration towards referee Michael Oliver, who allowed play to go on, despite a Liverpool player lying down holding their head.
The Sky Sports commentators confirmed after play restarted that Oliver and his assistants hadn't seen Mac Allister was down with a head injury, and as there was no foul in the build-up, VAR wasn't able to intervene. However, given the proximity of the incident and Mbeumo being played through, it would've been just as controversial to have blown up.
Ex-Liverpool star Stephen Warnock agreed with the Reds boss, saying on BBC 5 Live: "Going back to the head injury that Mac Allister received, it was from an elbow by Van Dijk, his own player. That doesn't matter, play should still be stopped for a head injury. Manchester United won't care."
It's the latest in a growing list of frustrations with officials for Slot, who was given a two-match ban last season for confronting Oliver after the Merseyside derby. Everton had equalised late on during the final Merseyside derby at Goodison Park, with Slot said to have told Oliver: "If we don't win the league, I'll [expletive] blame you."
Slot challenged the alleged expletive, suggesting he instead said: "If we don't win the league, I will have you to thank for that". Alas, the punishment remained, with Slot unlikely to have forgotten the pair's fiery interaction.
The early Mbeumo goal stunted Liverpool, with the Premier League champions huffing and puffing throughout the first half. They did hit the woodwork twice, but both efforts came via Cody Gakpo, who was the only Liverpool attacker to have properly threatened throughout the opening 45 minutes.
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