Roy Keane warned Ian Harte he would 'f***ing smash' him ahead of an imminent game between Manchester United and Leeds while the pair were having drinks as international teammates, the former Republic of Ireland defender has claimed.
The long-serving duo spent almost a decade alongside each other for their country – and on one of those camps, in 2001, Harte says he 'sobered up and went to bed' after Keane issued a crude threat of violence against him.
Recalling an incident he says happened in 2001 shortly before a game between United and Leeds, Harte told FourFourTwo: 'Back when we both played for Ireland, we'd sometimes go for a drink together.
'After one night out, we got back to the hotel – Leeds were due to play Manchester United on the Saturday.
'Roy turns around and says, "Hartey, you're a great lad. But when we play you at the weekend, I'm gonna f***ing smash you!"
'I sobered up straight away and went to bed. I love Roy, though – I've got so much respect for him.'
Hardman Keane was at the centre of several notorious flashpoints between the two clubs, who often have little love lost for each other.
Arguably the most notorious of those came in 1997, when Leeds' Alf-Inge Haaland stood over Keane to berate him despite the fact that the future Republic of Ireland boss had suffered an anterior cruciate ligament injury.
Keane took revenge on Haaland with a horror derby in a Manchester derby two years later – and he was rarely shy to take centre stage during skirmishes against Leeds.
Harte, who also played for Keane when the seven-time Premier League winner was Sunderland manager in the Premier League during the 2007-08 campaign, said: 'I didn't play much [at the Stadium of Light] but it was one of those things.
'I respected Roy as a player but, as a manager, he could have done things differently.'