ALEX MCLEISH insists Mark Warburton and Brendan Rodgers will have to put their friendship to one side when they go head-to-head on Saturday.

The former Watford colleagues will be reunited at Parkhead as the Old Firm meet for the first time in the Premiership this term.

Warburton has a victory over Celtic to his credit already after his side beat their Glasgow rivals in the Scottish Cup semi-finals last season but it will be a derby debut for Rodgers as he looks to continue his impressive start to life in green and white.

Read more: Alex McLeish: Rangers can lay down a marker of Premiership title ambitions with Old Firm winGlasgow Times: Alex McLeish

The Gers boss worked in the Academy at Vicarage Road when Rodgers started out his managerial career with the Hornets eight years ago.

And former Ibrox boss McLeish knows what it is like to come up against a familiar face on the opposite side of the Old Firm divide.

He told SportTimes: “I remember when Gordon Strachan came into Celtic he said to me ‘we will need to go out with the wives, Alex’. We never quite got round to it!

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“These clubs consume your life and it was very difficult for us to see each other privately.

“You tend not to do it but it doesn’t stop you being great football friends. It is the quirkiness of football.

“I went up against my gaffer, Alex Ferguson, a few times and you think ‘is this really happening?’

“It is a bit surreal when he is in the other dugout and I am in mine. That is just the way of football. You inevitably come up against someone that you have worked under or you come up against a close pal.

“During that 90 minutes, he is not your pal because you want to do everything that you can to win.”