WHEN Alex McLeish turned to his bench at a chilly Station Park some 21 years ago and beckoned forward a young goalkeeper for his debut, little did he know that he was about to set in motion the Rangers career of a club great. And far less that said player would still be between the sticks at Ibrox to this day.

Allan McGregor came on in place of Stefan Klos for the final 15 minutes or so of a routine 6-0 Scottish Cup win over Forfar Athletic, a less than glamorous start to the career of one of the most decorated and feted goalkeepers in Rangers history.

The outing was a reward not only for the undoubted ability being showcased by the fledgling keeper, but the drive he was showing day in, day out as he strived to improve and worked relentlessly towards making the Ibrox number one jersey his own.

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McLeish would be lying if he said he knew what was to follow for McGregor that afternoon in Angus, but there were clues to where he was heading in his application and desire.

“It’s hard to say you spot something in a young player and immediately believe he’s going to have a tremendous career,” McLeish said.

“People also ask me about (Mikel) Arteta. But you talk about a person’s attitude and that they deserve it for that.

“And at the time Allan so wanted it, he was so into the zone of wanting to be Rangers’ number one goalkeeper.

“The coaches at the time said the same thing. That his attitude was absolutely brilliant.

“A lot of the time the goalies are separate from where you’re working on the training ground with the rest of the first team. At different times you can work with the first goalie and the second goalie.

“Giving Greegsy his wee shot at that time was his reward but also for the coaches who had reared him.

“I think it was big Billy Thomson at the time - God rest his soul - and you get the feedback from him and others. Saying that Allan was an absolute beast of a trainer, wanting to work all the time and constantly asking questions. Even moaning at people.

“The word was he was just a brilliant kid. I’m so delighted for him how his career’s worked out and his reward’s the testimonial.”

That McGregor has always been a natural moaner is hardly revelatory given his on-field demeanour even now, but that quality is indicative of the will to win and the demands he places on himself and his teammates. A quality sure to be on show at Hampden today as Rangers try to salvage something from their season against Celtic.

“Allan hasn’t mellowed,” McLeish said. “If anything, he’s probably got worse.”

Would that approach have led to some disagreements had McLeish being operating in front of McGregor rather than the normally more placid Jim Leighton in his own playing heyday?

“If it had been me and Willie (Miller) then definitely!” he said.

“Back in the day, Jim could dish it out as well. Maybe in a different way.

“Sir Alex said to Jim ‘Just you stay in your f****** line...they two in front of you will get anything that comes in. Anything that goes beyond them you’ve got to save it!’ That was slightly different tactics and style of play.

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“But, Greegsy, even seeing him now, if somebody takes a shot, he’s moaning at the players for not stopping the shot. However, I’m thinking ‘Wait a minute Greegsy, at some time you’ve got to make a save.’”

When he is called into action, McGregor has shown at times this season he still has a shot-stopping ability that few can match, but there have also been errors that have led some to question whether it is now time for the 41-year-old to finally hang up his gloves.

McLeish has spoken to McGregor recently about his immediate future, and says it won’t be easy for Rangers to fill those gloves if he does decide to call it a day this summer.

“First and foremost, you need a black book of goalkeepers, knowing who’s going to replace him,” he said.

“Greegsy, I spoke to him about this a few weeks ago about this and said if you feel you can still do this, you have to believe that.

“I knew that I had to chuck it when I was playing myself every week in the Motherwell team as player-manager.

“I thought, ‘wait a minute, I can’t jump anymore, I can’t run anymore and I need to get John Philliben back in the team because there’s a good guy sitting on the sidelines’. I was kidding myself on.

“I think you know yourself and I think Greegsy is smart enough to know when he has to chuck it.”

Rangers manager Michael Beale has already started on his succession planning it seems, with Jack Butland linked with a move to Ibrox this week.

The 30-year-old is currently on loan as a back-up keeper at Manchester United from Crystal Palace, but having worked with Butland earlier in his career, McLeish feels his lack of frontline exposure of late won’t necessarily be a hindrance to him succeeding at Rangers should he indeed make the switch.

“I had Jack at Birmingham as a kid,” he said.

“He hasn’t been in action at the top level for a while and to come to Rangers, people get a rude awakening when they realise just how much the club has to win.

“I guess with the experience he has, he would have the capability and mentality to handle it.

“Jack was a good kid at the time, he had really great potential. He hasn’t been to the fore in the last couple of years.

“Coming to a club like Rangers, you have to win every week and save every ball. It’s different and a big, strong mentality is required.”

Alex McLeish was promoting Viaplay’s live and exclusive coverage of Rangers v Celtic this afternoon. Viaplay is offering a special limited-time offer for Scottish football fans available until Sunday only. Visit viaplay.com for more information.