STILIYAN Petrov, the former Celtic and Bulgarian captain, believes that Kieran Tierney’s exit from Celtic is an inevitability given the full-back’s consistency.

The 21-year-old has captained both club and country and Petrov expects that his growing maturation as a player has marked him out as an authentic target for the English Premier League.

Tierney has been scouted by a number of clubs, Spurs, Arsenal and Manchester United among them, and although he has contracted to Celtic on a long-term deal that runs until 2023 there is a feeling that sooner or later the club’s resolve will be tested.

“You don’t go under the radar if you are not consistently one of the top performers on the pitch,” said Petrov. “I don’t know if it will be this summer or next but I do think that at some point Celtic’s resolve will be tested.

Evening Times:

READ MORE: Robertson: Craig Levein faces huge burden of trying to deliver success at Hearts

“And if a huge offer comes in then the reality is that you have to take it. It will take big money to get him. I don’t know how much that will be but it will be no problem for a Manchester United or whatever.

“Right now the boy just has to keep doing what he is doing. Getting into the Champions League can be so important for his development because you learn so much when you are in that environment and playing against the best.”

And Petrov believes that making the right move for Tierney could enable him to fulfil what he regards as “world-class” potential. The 21-year-old’s ability to thrive under pressure is also a key attribute for making a mark in the upper echelons of the game, according to Petrov.

“He has the potential to go on and be world-class,” said Petrov. “I honestly believe that. He could go to a Manchester United or any other top level club because he has been brought up having to play under pressure.

READ MORE: Johan Mjallby: Neil Lennon a safer bet for Celtic than Roberto Martinez or Andre Villas-Boas

“Like all good players he has not just survived in that environment but has flourished and those who have the temperament to deal with that are the guys who make it to the top.

“He has shown he can cope at European level. In the Champions League he has been excellent. But it is also about the way he behaves on the pitch. He has shown that he is a leader.

“He has captained his country and he has captained Celtic. That is special for being only 21 years old.

“He will get better all the time and as an ex-Celtic player and a Celtic fan I want to say that I want him to be at Celtic for as long as possible. But that is not how football works.”

Meanwhile, Petrov believes Neil Lennon has the characteristics to assume the Celtic job on a full-time basis this summer, despite a number of the Parkhead supporters urging the club to broaden their scope.

“I played with Neil Lennon for a chunk of my career and the one thing you can say about him is that he is a winner,” said Petrov. “I think you have to look at the way he took the job. How many people would have wanted to step into Brendan’s shoes? Those would have felt like pretty shoes to fill. So the very fact that he didn’t pause for a second but went straight in and took it at a very difficult time for the club tells you so much about him.

Evening Times:

READ MORE: Derek McInnes knew Lewis Ferguson would be a success at Aberdeen but not what foot he kicked with

“There is always going to some division within the support. In some ways that comes from having got a name like Brendan in so there is a feeling that by giving it to Lennon it is somehow not as big a name but I think that is unfair. Neil has won games as Celtic captain, he has won as Celtic manager and he enjoyed some pretty big European results in his first time around as manager. He has won leagues. He has won Cups. I don’t know who else would better him in terms of understanding the club and understanding the pressures around it. He sustained the club when the season was in danger of collapsing.”