Rangers legend Stuart McCall believes that his former side can challenge for the Premiership title next season, and he has warned Celtic that they will have to strengthen in the summer if they are to fend off the challenge of the Ibrox side along with Aberdeen and Hearts.

McCall, who was speaking on behalf of BT Sport, believes that Celtic have regressed in the years since Rangers’ liquidation in 2012, and he is expecting Mark Warburton to be given significant money to bolster his squad for their tilt at next season’s Premiership.

With the gap between the champions and the rest narrowing, the former Motherwell manager is excited by the prospect of a four-way title race next term that might include Rangers, should they be promoted as expected.

He said: “There’s no doubt Rangers have got real momentum now. Hearts and Aberdeen are getting stronger too so it’s got the makings of a really good season.

“It all depends what happens in the summer. Rangers will have lots of sell-outs next season and with things like corporate hospitality their finances will be strong again.

“It was only two months ago Rangers punters were saying they hadn’t spent enough money, but they spent what they needed to. I remember saying to Dave King at the time that you don’t need to spend fortunes to get out of the Championship.

“You don’t have to go and throw loads and loads of money and pay massive wages to get out of that division, you can wait until you are up there. In that time, are you just putting a nest-egg together to have a real crack at it when you get to the Premiership?

“I think Celtic will have to strengthen. It looks like James Forrest will move on and Charlie Mulgrew hasn’t been offered a new deal, so there will be changes there. They’ve got a lot of bodies.

“If you listen to Celtic supporters, the club may have managed to win some league titles, but I’m sure the supporters and the club would have expected more trophies.

“When I was at Motherwell, Celtic had [Joe] Ledley, Ki [Sung-Yeung], [Victor] Wanyama, [Virgil] Van Dijk and [Fraser] Forster – all playing at good Premiership sides – as well as [Gary] Hooper and [Beram] Kayal who are playing at the top end of the Championship, so they were a strong side back then.

“They might have missed a trick when you look at the sides who have won trophies in that period.

“Celtic haven’t spent the money of previous years and they’ve increasingly gone down the younger route. We’ve seen in the last twelve months that it is young Scottish boys like [Ryan] Christie, [Stuart] Armstrong, [Gary] Mackay-Steven and [Scott] Allan that they’ve brought in, and if they don’t win the league this year there will be trouble.

“It will hot up even more next season. It is going to be really interesting with Rangers back, Aberdeen strong and Hearts still improving. Those teams can spend a bit more because they’re getting crowds in now, which will make them stronger.

“Hearts are getting sell-outs every time now and Aberdeen are getting big crowds. They’ve brought better players in and the league should be really competitive with big fan bases that generate finances.”

McCall finds ongoing speculation around Celtic manager Ronny Deila’s future a little distasteful, believing that managers who are interested in the position should respect the man currently in situ.

He is intrigued however by a potential return to the Celtic Park dugout for former manager Neil Lennon following his departure from Bolton Wanderers, believing that he may be tempted to return to Glasgow as his own former boss Walter Smith was in 2007, to add a further layer of interest to next season’s title race.

“I think everyone in the game would say it is unfair for a manager to discuss another manager’s position when he’s still in a job,” he said.

“If Ronny’s contract was coming to an end in the summer like Walter’s was all those years ago and you knew he was leaving in the summer then it would be easier to talk about it.

“I know Neil thought the time was right to get out, but then Walter went back to Rangers, so you never know.

“I think Neil wanted to get out of the goldfish bowl and have a crack at England, but for lots of different reasons it hasn’t quite worked out for him. It would be tough for him to turn down, I’m sure he misses it

“Anyone looking at the Celtic job – if it becomes available – will of course see it as a great challenge.

“Things can change so quickly in football, look at [Jose] Mourinho and what has happened to him in four months, no one could have seen that coming.

“Even Alan Stubbs was flying but then Hibs lost four games out of five, so they won’t finish top now.

“Ronny could actually win the double, but that might not be good enough for the supporters.”

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