Sir Alex Ferguson's main enemy throughout his illustrious 26-year tenure as Manchester United boss was undoubtedly Liverpool.
The former United manager infamously vowed to "knock Liverpool off their f****** perch" in 2002 and was rarely in for a warm welcome whenever he made the trip to Anfield.
But his relationship with one former Reds star was particularly frosty for the best part of two decades after he accidently overheard a joke made at his expense.
Gary McAllister won a cup treble while a Liverpool player, and played vital roles in both their League Cup and FA Cup triumphs in 2001. But it was an incident that occurred while he was still at Leeds that sparked a fallout with Ferguson.
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Having spent six seasons with Leeds in the nineties, McAllister helped United's Elland Road rivals win the first division in 1991/92 as they became the final champions of England before the inaugural Premier League season.
After Leeds had registered a 3-2 victory over Sheffield United earlier on in the day, Liverpool had beaten United 2-0 in the penultimate game of the season to help secure the title victory.
Following their win over the Blades, McAllister watched the United vs Liverpool clash at the home of Lee Chapman alongside Eric Cantona, David Batty and a television crew.
Once Liverpool's win over united had been confirmed, the trio of Leeds players started to celebrate while still McAllister was still wired to the television studio.
A comment made by the former Scotland international during said broadcast would lead to a lengthy breakdown in his relationship with Ferguson for the next 20 years.
"We all went back to Chappy’s house after the game in Sheffield to watch Man U play Liverpool at Anfield," told fans in association with Sport & Fitness Middle East back in 2017.
"Because I’d done some TV work, I was tuned in to the director at Anfield so I could hear the director and all his comments, talking to the presenter, talking to the cameramen. I could hear everything which was going on in the studio.
"Liverpool win 2-0 and Leeds United win the league, we’re p****d. After the game, we’re watching the pictures coming across and the interviews after the game and I can hear in my ear the director saying, “Get to the tunnel, we’ve got Fergie."
"Milliseconds later he’s up on the TV and Fergie comes on. His face is bright red.
"His first comments, as you can expect, were, 'I want to make it clear, Leeds haven’t won the league. Manchester United have lost the league! I’m making it clear!'
"Nose very red, he says, 'Make no mistake, Leeds have not won the league! Manchester United have lost the league! We’ve thrown the league away.'
"So flippantly in Lee Chapman’s living room, I say, 'Big red-face as gracious as ever in defeat.'
"Then Dennis Law came back in my ear and said, 'Gary, Fergie can hear you.'
"Alex Ferguson has walked past me in Lithuanian airports and Albanian hotels for 20 years and never looked in my direction!"
Thankfully, the pair eventually ended their feud after Ferguson contacted McAllister following the death of his wife Denise in 2006.
"This is the measure of the man. When you’re competing against him, you’re the enemy, but when I went through this tragic experience with cancer, who was the first person to call me? Alex Ferguson," McAllister added.
"He was the first person to make a phone call. He invited me to the training ground at Carrington. He said, “You can come to training any day. You can come to Old Trafford to any game.”
"The first mass card I got through the post was from his wife. You see this figure, when you’re competing against him, he’ll do anything to beat you.
"But there’s a gentle side to Alex Ferguson and that’s something I learned down the line. For 20 years, I did not exist!"
