Former referee explains the key decisions in Sunderland's controversial defeat to Swansea City

Foy also said that Stroud was not to award the Black Cats a penalty for a challenge on Amad seconds previous - though he said this was a better claim than that of Dan Neil when he went down early in the second half.

O'Nien's late challenge on Ollie Cooper in the 20th minute proved to be a crucial moment in the game, with Russell Martin's side going to to run out 3-1 winners in the second half.

Foy spoke to the EFL website to explain some of the key decisions over the weekend's league fixtures, and said that O'Nien had 'clearly' challenged with excessive force, leaving Stroud with 'no option'.

Foy said: "Player safety is paramount when officiating, and as such I think this one is a straightforward decision – the tackle was late and made with excessive force, leaving the referee with no option but to show him a red card for serious foul play.

"I think it is also worth mentioning the two penalty appeals in this fixture, both of which I believe did not meet the threshold for penalising. Whilst there was more contact in the first challenge, I do not believe either should have resulted in a penalty being awarded."

Russell Martin said afterwards that the red card was 'clear as day', while Tony Mowbray said he felt the ferocity of O'Nien's challenge had been key and backed him not to repeat the mistake in future.