Manchester United and Arsenal's rivalry in the 1990s and 2000s was legendary.

To say that the two sides hated each other would be an understatement.

There were scuffles and bad challenges galore whenever they came up against each other on the field.

The two players almost always involved in those scuffles were Roy Keane and Patrick Vieira.

Keane and Vieira did not like each other at all. They were both fierce competitions clashed almost every single time they played each other.

The last time they lined up on opposite sides came back in 2005.

Their relationship has improved drastically since then and they now get on well.

22 Aug 1999: Roy Keane of Manchester United clashes with Patrick Vieira of Arsenal during the FA Carling Premiership match against Arsenal played at Highbury in London, England. The match finished in a 2-1 win to Manchester United. \ Mandatory Credit:Clive Brunskill /Allsport

But Keane still isn't afraid to troll his old rival from time to time. And he did so before Arsenal's loss to to Chelsea in August 24.

Keane was working as a pundit for Sky Sports and was pitch-side at the Emirates Stadium ahead of the match.

An Arsenal fan asked decided to have some fun and ask Keane 'Where's Vieira?'

The Irishman then gestured that Vieira is in his pocket before letting out a cheeky smirk.

What a character Keane is. He truly is the gift that keeps on giving.

Both Keane and Vieira will no doubt be casting a keen eye as Arsenal and Manchester United meet at the Emirates Stadium in a crucial Premier League clash on Saturday afternoon.

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The two sides, as well as Tottenham Hotspur, are fighting for the fourth and final Champions League berth.

United are currently sixth and three points behind Tottenham and Arsenal having played a game more.

The game has massive implications and it's set to be a fascinating encounter.

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