I doubt it helps Sunderland's case that Coleman said it was a tackle that gave the referee a decision to make. He said he'd seen reds given and not given for similar incidents. So after reviewing the footage the Sunderland manager basically agreed a red card was an option in that situation. Then they decide to appeal!

I can see how it was a straight red, but would not have been surprised if it was just a yellow. What causes a problem is when different referees make totally different judgements about very similar incidents. In the Steel City Derby on Friday Ross Wallace went very high on John Fleck (without the excuse of sliding off the top of the ball) and got away with a yellow. It was worse than the Ndong foul but all the same issues came into play - control, danger, recklessness, intent.