The 2-1 defeat in the Olympic Stadium was caused by the loss of two preventable goals and Petrov believes that Celtic would be playing off for a place in the primary tournament next week – instead of in the Europa League if Boyata had been in the heart of their defence.
The Bulgarian insists that, whether or not Boyata – who is in the final season of his contract at Parkhead – is sold before the transfer window closes at the end of the month, he will be frozen out in the dressing room after abandoning his former friends.
“If he could have played and he didn’t then, as a team-mate, I would have felt letdown,” he said. “You owe it to your teammates and the people you work with every single day. If you let them down then it is very difficult to come back from that and earn their trust again.
“The next step for the board and manager is to see what is right for Celtic – sell him and bring in two other central defenders.
“There’s definitely a friction in the club. Dedryck has been very good for Celtic, he’s been a strong player for them, he’s been at the heart of the defence and he’ll be a big miss; we saw that against AEK. But when you lose the trust of the players and your manager it’s very difficult to get that back.
“I hope they find the best outcome for Celtic because managers and players come and go but the fans and the club stay. He’ll either go or stay. If he stays it’ll be very difficult but we’ve seen a lot of twists and turns in football.”
Petrov compared Boyata’s behaviour unfavourably with the more dignified approach he adopted when attempting to manoeuvre a move to England 13 years ago.
“I had the same situation with (former manager) Gordon Strachan,” he said. “I wanted to go but Gordon was brilliant with me because he said: ‘I need you for another six months’. So we had an agreement and we decided I’d sign another contract and, if I played well, the club would get money.
“We had just signed Shunsuke Nakamura and I would help integrate him into the side. We also had young Aiden McGeady and Shaun Maloney and Gordon wanted me to help them and show them the way you act as a Celtic player and I agreed to that.
“Was I happy or not happy? It doesn’t matter any more. I had an agreement with that manager, I knew what was coming, I knew what I needed to do and, for six months, I played some of my best football. Gordon was happy and – six months later – we shook hands. The club got what they deserved and I left for the Premier League, which is what I wanted.”
Petrov also poured scorn on the behaviour of Boyata’s agent, Jacques Lichtenstein, who told Rodgers that his client would not play and risk injury while the prospect of a transfer remained.
“I think he was badly advised,” he said. “I’ve read all about his agent going to the training ground. I’ve seen things like that happen before. I’ve had a number of agents and seen it all so I’m not surprised by that.
“Sometimes, if things don’t go the way you want it, you get the player trying to force it and you don’t get the outcome that you want. That’s where you get the friction and a problem between the club and the player.”
l Stiliyan Petrov yesterday launched A Match for Cancer which will take place at Celtic Park on Saturday, 8 September. Tickets are now on sale priced £14 for adults and £6 for concessions.