The keepers head was low as much as the players foot high in my opinion, i don't think it was dangerous play as Mane raises his leg away from the keeper towards the flight of the ball, the keeper stoops his head forward and down into Mane's run and his attempt to get the ball, stupid and dangerous of the goalie to stoop low with his head in a 50/50. If Mane had stooped down with his head as the keeper tried to kick it and got Mane instead would the ref have sent him off? I don't think he would have. It was a 50/50 there to be won, the keeper got a whack in an accidental coming together, thats footie, it happens. If you watch the replay the ref reacts to the city players grabbing their faces and waving to the bench Otamendi in particular, they made his mind up for him he should have given himself some space to think it through. That wasn't the only decision the ref got wrong either how was Trents foul on De Bruyne a yellow yet Sane's on Moreno was a telling off, the shove on Wijnaldum in the lead up to their goal, totally missed Klavans handball as well among others, he had a shocker and should be demoted it was an awful performance by the ref.