The Hoops manager's stock is high after he overhauled Rangers in his first season in charge to reclaim the Scottish Premiership title, while also implementing an eye-catching front-foot playing style.

The popular former Parkhead midfielder Petrov is adamant Postecoglou will now be fully focused on making sure the Hoops are equipped to turn on the style when they compete in the group stage of Europe's elite competition for the first time since 2017.

"Ange Postecoglou came with a different style of play and different demands for the players," Petrov told Sky Sports.

"The fans enjoy watching the way they play. They play with a free flow.

"It's going to be important for him to do well in the Champions League.

"That's where he needs to stamp his authority and show everybody how good he is as a manager because that's where everybody's watching and, globally, everybody wants to see Celtic doing well.

"He'll make sure he plays the football he believes in and he'll make sure Celtic will be the team everybody's talking about because he always says this is the next step.

"He's done it in the league and now the next thing is about Europe. He's fully concentrated on doing well in the Champions League."

Celtic have been quiet in the transfer market so far this summer, with Cameron Carter-Vickers signed on a permanent deal from Tottenham and goalkeeper Ben Siegrist joining from Dundee United.

But Petrov is confident Postecoglou will soon land further new recruits to elevate the quality of the squad ahead of their Champions League tilt.

"I think he recruited very well last season and, at the moment, it is really important to get the right players for the right positions because the Champions League is just around the corner," said Petrov.

"He has to be ready. He knows that if he wants to play well and preach the football he did last season, he has to have the right quality of players this season.

"He will do that because it seems the fans and board believe in his judgement and he will have the right players not just to compete in the Champions League but also to win the championship as well."

Australian Associated Press