When one thinks of the relentless winning culture at Manchester United in the 1990s, two men above all perhaps epitomise it: Alex Ferguson and Roy Keane.

As much is said by Ole Gunnar Solskjaer in Prime Video's new 99 documentary on the famous Treble-winning season of 1998-99. Solskjaer says that, before winning over the rest of the squad, new signings had to be sure to meet the standards of Fergie and Keano.

The '99 season was among Keane's finest in a United jersey, as he captained the club to an unprecedented Treble of league, cup and continental glory.

It is one of the few weak points of the excellent new Prime Video doc that Keane could not be convinced to take part, though there is involvement from almost all of his teammates from that iconic campaign.

Given the influential role Keane played in that campaign, it is no surprise that he nonetheless holds a major presence in the documentary - with Gary Neville among those hailing his rousing speech at a wild Christmas party as a pivotal turning point in the squad's psyche that season.

Manchester United teammates hail Roy Keane's Christmas speech as '99 turning point Though Manchester United's 1998-99 season remains one of the greatest achievements in English football history, it was not as plain-sailing as many might have remembered.

Defeats to Sheffield Wednesday and Middlesbrough late 1998 had them in 3rd on Christmas Day, scrambling to keep up with Arsene Wenger's Arsenal, the defending Double champions.

We needed some fun...the lads needed to release some of that tension that was building up. The Christmas party was a proper Christmas party. I've been at a few Christmas parties, but nothing like this one.

When we got there, the boys could not believe how many people were there. It was just crazy. It was the best night.

People who never drank drank - I can tell you that. It got messy.

It certainly seems to have been a wild and rowdy night, after a tense beginning to the season had seen United cling to the title race and progress in Europe - both by the skin of their teeth.

Yorke says that captain Roy Keane was part of the organising committee for the party. Another member of that committee, Gary Neville, says that a speech from Keane at the end of the night "galvanised" everyone.

Neville's initial comment comes across as tongue-in-cheek, but it becomes clear from his fellow squad members that this was genuinely a pivotal moment for squad morale.

Denis Irwin: He grabbed us by the scruff of the neck. Everybody knew what he was getting across.

Gary Neville: "Enough is enough. Sort this out, we need to start now."

Peter Schmeichel: "We can't do this, we can't play like this, that's not who we are, we're a lot better than this." So, what we did was we agreed that we would not lose again. Once we'd made that kind of commitment to each other, it pushed us in the right frame of mind again.

By all accounts, the United Christmas party of 1998 appears to have been a drunken affair - which makes it all the more notable that so many squad members can vividly remember Roy Keane's end-of-night speech.

Maybe all any team needs for a bit of success is a drunken team talk from Keano.

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