Ferguson reveals in 2005 that Keane was livid at the club over their pre-season training camp in Portugal. The Irish midfielder said the accommodation was not up to scratch.
Then Keane tore into his team-mates in an interview with the club's in-house TV station MUTV.
Ferguson says in the interview, which was pulled, Keane "slaughtered" several of the club's senior players.
Keane then suggested the squad watch the interview and a furious row ensued. Ruud van Nistelrooy, Edwin van der Sar and Carlos Queiroz all argued and Keane then accused Ferguson of bringing his own dispute with shareholder John Magnier over the Rock of Gibraltar racehorse into the club.
"It was frightening to watch. And I'm from Glasgow," Ferguson says.
"He has the most savage tongue you can imagine."
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