Roy Keane made a brutal comment about Sir Alex Ferguson during Man United vs Man City quiz

Roy Keane aimed a brutal comment at Sir Alex Ferguson during a Manchester United vs Manchester City quiz.

Keane was a guest on a quiz on former teammate Gary Neville's 'The Overlap' channel, competing against pundit pal Micah Richards and former City and England women's star Jill Scott.

Both teams had to answer some seriously difficult questions about Manchester derbies ahead of the FA Cup final showdown between the two sides at Wembley on Saturday.

One question for Keane and Neville was to correctly name the score for the first derby they started together, in the 1995/1996 season.

The two got a little mixed up and thought the game was at Maine Road, with Neville believing it was the game where David Beckham scored a free-kick winner and Sir Alex Ferguson was not in attendance back in 2000.

Scott was curious as to why Ferguson wasn't in the dug-out, and Keane, who he was on top form throughout, had a dig at the Scot.

“His son was getting married,” Keane explained

Obviously… because he always done what was right for Man United but he obviously went to his son’s wedding, yeah, erm…”

The Irishman has said he would never forgive his long-time manager.

While Keane and Neville got the game in question wrong - and even rinsed assistant manager Steve McClaren - the score for their first derby game together was indeed 1-0 as they guessed and they got the point.

Paul Scholes struck the only goal of the game four minutes into the clash at Old Trafford.