The Man United fans have seen a lot of falling outs during their time but none have been as big and as long-standing as the Sir Alex-vs-Roy Keane battle.
The duo worked together at the club for one full decade and for the most part of it, Keane was the leader on the pitch while Sir Alex was the leader of it.
But their relationship slowly broke down over time and before Keane was released by Man United, there was a very public spat between the pair.
And even after 14 long years, Roy Keane still holds a massive grudge against his former Man United manager and recently the club legend launched a scathing attack at his ex-boss.
“People talk about Ferguson’s man-management – don’t be kidded on by all of it,” Keane told Off The Ball[as quoted by Goal].
“I was at the club when Bryan Robson left, when Steve Bruce left, two brilliant servants for Manchester United, and I didn’t like the way they were treated.
“We’d had loads of heated discussions over the years, sometimes as a team, but you’ve got to roll with that,
“We’re grown men fighting for the same thing. There’s going to be a bit of argy-bargy but I’m sure there are people here working in industries where things get heated.
“I didn’t leave the office that day thinking this was the end of my career at Manchester United, but if you think I’m going to sit there, I don’t care if its Alex Ferguson or the Pope… I’m going to fight my corner.
“Ferguson came out afterwards and said he always did what was best by Manchester United. Nonsense. His son Darren played for the club and won a league medal. [He was] very lucky.
“[Alex Ferguson’s] brother was the chief scout for Manchester United for a long time. I’m surprised his wife wasn’t involved in the staff somewhere.
“Darren was [the manager] at Preston North End and lost his job. He had a couple of young players on loan from Manchester United, [but] guess what happens the next day?
“They’re pulled out of Preston. Is that doing the best for Manchester United? Do me a favour.
“I think when he [Sir Alex Ferguson] apologises I will probably say hello to him but I’ve no interest in speaking to the man.”