Celtic hero Stiliyan Petrov has opened up on John Barnes' times as manager of the club, claiming "there was always fighting" going on between the players.

The Bulgarian was signed by the former England international in 1999, who was undertaking his first job in management, but things quickly started to go pear-shaped.

Barnes only lasted eight months and was sacked after the Parkhead side's Scottish Cup defeat to Inverness.

And Petrov has detailed the toxic atmosphere in the dressing room at that time.

Speaking to FourFourTwo, he said: "I couldn't understand much of what was going on, due to the language barrier, but there was always fighting.

"I could see little cliques and problems. He couldn't control the powerful characters. It was John's first job since retiring as a player, and a big one for him.

"The team was winning, but we had many internal issues. The players weren't giving everything for him.

"Sometimes a job can come a bit too early for someone, but that doesn't mean they're a bad manager."

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Meanwhile, ex-England international Trevor Sinclair has praised Celtic boss Ange Postecoglou, calling him "brilliant".

The 50-year-old spoke about the Australian after participating in a Legends match between Liverpool and the Hoops at Anfield.

And he had nothing but good things to say about Postecoglou's time at Parkhead so far.

"Could he leave a legend? Absolutely – as long as it’s not in the middle of the season, I’ll say no more on that!

"Listen, he’s been brilliant for the football club. He’s a very humble man, I think he’s quite shy actually.

"You see his speech after winning the first championship – we never stop – it’s almost like a motto for the football club now.

"I absolutely love the club from top to bottom and it’s great to have someone like him in charge.

"The style of football will attract a lot of Premier League interest. But then there’s the way he’s so competent in front of the media, he sticks up for himself and the football club, speaks really well.

"He won’t let journalists or anyone bully him. From the moment he walked through the door, I’ve been so impressed with him.

"I spoke to a few of the boys and I don’t think he’s the most social, a bit standoffish. So obviously he holds his court and his rules in place.

"Long may it continue. How much boys are playing for him shows how much they respect him and what he brings to the table.”

"I’m a huge Ange fan. He suits the club so well."