Roy Keane was a brilliant player for Manchester United.
The Irishman was a fierce competitor and that made him a huge success during his time at the club.
He also had a very short temper. It didn't take much to wind him up.
On September 15, 2001, Newcastle welcomed United to St James' Park.
Newcastle won 4-3, with Wes Brown's 82nd minute own-goal proving to be the winner.
Keane was given a red card with moments remaining after an altercation with Shearer.
The Newcastle man absolutely rattled United's captain after the ball went out for a throw-in.
Keane was trying to take the throw quickly when Shearer pushed him.
The two then went head-to-head after the Irishman threw the ball at the Newcastle legend.
Words were exchanged and Keane lost his head. He appeared to swing for Shearer and was sent off.
He had to be held back by his teammates before making his way off the pitch.
So, what did Shearer say to wind Keane up so much?
Keane said in his autobiography, per PunditArena: “I grab the ball to take a throw-in. It’s injury-time, deep in our half. Shearer stops me from taking the throw-in. He’s taking the piss. I lose it, throw the fucking ball at him.
“'You p****,' he sneers. The way he says it, I know he really means it.
“I go for him, try to grab him by the throat. He’s grinning. ‘You p****.’ He gestures dismissively. The red card comes out. Shearer’s right. I am a p****. Fell into a trap.”
Shearer, meanwhile, revealed that Keane was waiting for him in the tunnel after the game.
He explained to The Athletic: “When the final whistle went, Roy was standing at the top of the stairs waiting for me. I’m pretty sure a few more choice words exchanged, there was some bustling and scrambling.
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“But there were way too many people between us for anything physical to actually happen. That’s usually how it pans out in football.”
Shearer wasn't the first person that Keane clashed with, and he certainly wasn't the last.