Graeme Souness believes Michael Beale should get time to get it right at Rangers following Champions League failure, but thinks the Gers boss cannot afford to lose Sunday’s Old Firm game.

The Light Blues were thrashed 5-1 in the second-leg of the play-off against PSV Eindhoven in Netherlands on Wednesday night to exit on a 7-3 aggregate and drop down to the Europa League.

Beale, who was assistant to former Gers manager Steven Gerrard, took over the Ibrox hot seat last November and an inquest into his tactics, selections and signings – he has recruited nine new players – began in the wake of the Dutch drubbing and ahead of the visit of Celtic, who lead Rangers by one point in the cinch Premiership.

In a talkSPORT interview, Souness, 70, player-manager of Rangers between 1986 and 1991, said: “It was a tough one to take last night. I’m a Rangers supporter and it was a hard watch.

“We’ve got a new manager and he’s obviously trying to implement new ideas on the group he is working with and he’s got several new faces.

“I watched both games and in the first game they (Rangers) got away with it.

“PSV were a good team on the front foot, not so good at defending, they’ll get beat up a few times in the Champions League by the better teams I would think.

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“It was just a step too far for this Rangers team. He’s brought new players in, (it) is still very early to pass judgement on them in terms of how they will do in the Scottish Premiership.

“He’s been there before with Steven Gerrard so he knows the pressures that come with being in the hot seat at Rangers.

“Getting beat up in midweek isn’t good for him, and if they came unstuck on Sunday that will put him under a hell of a lot of pressure.

“He is a relative newcomer to the hot seat. I’ve been there, I have managed big football clubs and Rangers is as big as any. The pressures that come with that job are enormous.

“You’ve got to batten down the hatches and take it on the chin because he will be we getting a lot of criticism this morning, and keep believing in what he’s doing.

“Do I believe in him long term? I wouldn’t be critical of him. I think it’s a hard job, I know how difficult that job is and we’ve got to give him time to get his team thinking the way he wants them to think and play the way he wants them to play. But it’s not an easy job he’s got. It’s a must-not-lose game I think.”