Former Celtic player Stiliyan Petrov has warned Rangers that his old club are set to record back-to-back trebles, and there is nothing that they can do about it.

The Hoops legend reckons that the gap between the city rivals is now so vast, that Brendan Rodgers can not only complete a domestic clean sweep this season, but go on to make it an unprecedented ‘double treble’.

Far from revelling in his assertion though, Petrov hopes that Rangers can get stronger and provide some sort of challenge to his old side, believing that each club needs the other to provide competition.

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“I’d say it’s a great opportunity for Celtic to do it,” Petrov said. “If Rangers don’t regroup and don’t get better and don’t start buying, which I think will be difficult to do given where they have come from and their financial difficulties, then there is big potential for Celtic to win the treble for the next couple of years.

“But I hope I’m wrong and Rangers come back to push Celtic. With the money that Celtic have got, if Rangers come back and push them and make it harder, they need to go and spend again and they will become even more powerful and that’s good for Scottish football.

"Celtic are way too strong for Scottish football right now. They have top players with power and pace. They will rule Scotland for years to come.

“Obviously, they need Rangers but Rangers have shown they are off the pace, big time.

"I appreciate a lot of what they have done, they have come from a very difficult position and having them back in the league is great.

"I hope they get better and better because these two teams need each other, they need to push each other.”

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Rangers full-back James Tavernier recently asserted that the Ibrox outfit had shown in the Hogmanay clash between the rivals that the gap between the pair had narrowed significantly.

But what Petrov saw in Celtic’s 2-1 triumph was a gulf that was as vast as ever, going as far to label the contest as “men against boys”.

And if the Champions League riches that rolled into the Celtic Park coffers this season do so again in the next campaign, then he can only see that disparity widening further still.

"What I saw in the last game was a big gap,” he said. “We had Rangers who tried for 25-30 minutes to give Celtic a game.

"But after that it was men against boys. Celtic were too strong, too powerful, too quick.

"No-one else will push Celtic, not Aberdeen or Hearts, anyone. No-one will get close. Financially and with the quality of players they are buying.

“They have money at the moment and they could end up selling more players – they have a lot of assets.”

Petrov hopes and expects the current Celtic squad to get over the line and emulate his own class of 2001 by sealing the first treble for the club in 16 years.

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With the league already seemingly secure and the League Cup in the trophy cabinet, the only potential stumbling block is the Scottish Cup, and Petrov warned it will be far from easy to claim the old trophy.

“I hope they win the treble because it would be a great achievement for every single player,” he said. “When you are a player and you win a treble it’s an incredible journey and I hope they do it.

“It’s not done yet though, everybody will try to go after them because they know they are the best and they are going to be the champions because it’s too big a gap to talk about anything else.

“So everyone is after them, and the cup is not like the league where it’s a marathon, so the cup will be difficult but I think they are on the right path.”