FORMER Ibrox manager Alex McLeish reckons Rangers bad boy Joey Barton must find his best form and quickly if he is still salvage a career at the Glasgow club.

A turbulent few months have defined the start of a light blue career that hangs in the balance after being banished from Murray Park before he was hit with a three-week ban for a post Old Firm row.

On top of that, reports emerged yesterday the midfielder was being investigated over betting allegations surrounding Celtic’s 7-0 drubbing in Barcelona.

Read more: I phoned Mark Warburton after Old Firm defeat and said 'Welcome to the Old Firm', reveals Alex McLeishGlasgow Times: 24/08/16 .  RANGERS TRAINING .  THE RANGERS FOOTBALL CENTRE - GLASGOW .  Rangers' Joey Barton.

As an ex-Gers boss and a coach who has also managed down south, McLeish was intrigued as Barton put pen to paper on a two-year Rangers deal in the summer.

But he admits that he has failed to show his best form as uncertainty clouds his future, and that he must prove himself on the park if he has a chance of winning round Mark Warburton and the Ibrox support.

Read more: Mark Warburton: Rangers will head to Pittodrie in high spirits after League Cup victory

“Well, I knew it was going to be colourful with Joey signing,” said McLeish. “You know, a lot of people underestimate what they’re coming to here.

“And I also believe, I know, that a lot of players have struggled to cope with playing for Rangers or Celtic.

“You think of Basile Boli coming. I can give you loads from both sides.

“Basile was a European champion who came and struggled in Scottish football, struggled at Rangers. Some players struggle to live up to the names of these clubs.

“I don’t think Joey is in the category of being overawed. Far from it.

“But I think he’ll be honest and say he’s not reached his level. Particularly after what he said.”

He added: “This is a tough league. You have to show your level – and you have to do it on the pitch.

“We’ve seen how Joey can play. I saw a few Burnley games last season and he really stood out for me.

“I thought he would come here and light it up. But, again, he’s got to find his best form – if he’s ever going to wear the jersey again.”

Barton’s fall out with the club has only added fuel to a fire that burns as Rangers’ season, even at this early stage, has offered little encouragement for the weeks and months ahead.

The Ibrox outfit has only two Ladbrokes Premiership victories to their name so far and after losing 5-1 to Celtic, could manage just a 0-0 draw with Ross County at Ibrox at the weekend.

It is a difficult situation that McLeish concedes has been made worse by the Barton bust up.

Read more: I phoned Mark Warburton after Old Firm defeat and said 'Welcome to the Old Firm', reveals Alex McLeish

“They don’t need that,” said the former Scotland boss, who was promoting BT Sport’s coverage of the Betfred Cup quarter-finals. “And they have to try to suppress that.

“I don’t know what the outcome is going to be there.

“People are speculating about Joey not pulling on the blue jersey again. We have to wait and hear all the facts.

“Well, how have they dealt with it?

“I think they’ve got to protect Rangers, first and foremost.

“I think Mark is doing that.”

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