Former Liverpool captain Steven Gerrard agrees with Chelsea manager Jose Mourinho that Mario Balotelli is "unmanageable."
Balotelli, 25, has been loaned to AC Milan after struggling to make an impact at Liverpool following his move from the San Siro in 2014 -- and he impressed in the Milan derby on Sunday night despite a 1-0 loss to Inter.
The Italy international played under Mourinho when the Portuguese was in charge of Inter Milan, and in 2010 he warned clubs about his poor attitude.
Gerrard said in his book "My Story," which is being serialised in the Daily Mail: "After his promising debut against Tottenham, he had lapsed in training and the subsequent games. His demeanour was very poor. I made my up mind pretty quickly after that about Balotelli.
"We got on fine. I still tried to help him and I kept looking for chances to praise him but I could see why Mourinho had been right when he said Balotelli is unmanageable.
"He is very talented with the potential to be world class, but he'll never get there because of his mentality and the people around him. Balotelli's always late, he always wants attention."
Gerrard was unimpressed with the way Balotelli, who has scored four goals in 28 appearances for Brendan Rodgers' Liverpool, conducted himself in training.
The LA Galaxy midfielder said: "He made an immediate impression when we were doing work on our defensive set pieces and Balotelli said to Brendan: 'I don't mark on corners. I can't.'
"I nearly fell into the goalpost. I was thinking, 'What are you? 6-foot-3, and one of the strongest men I've ever seen on a football pitch? And you can't mark on a corner?'
"Brendan was very firm. He said to Balotelli: 'Well, you can now -- and if you can't then you're going to learn.'
"That was the first conflict between Brendan and Balotelli, on day one, but the manager stood up to Mario really well. From that point, Balotelli started marking on corners."
The ex-England captain added: "In my last season, Brendan Rodgers came to me at Melwood one day in mid-August. We had a chat on the training pitch.
"He said, 'You know we've missed out on a couple of signings. I'm basically left with no option but to have a bit of a gamble.'
"Brendan paused before he spoke again: 'The gamble is Mario Balotelli.' My instant reaction was, 'Uh-oh.' I'd never met Balotelli but I'd heard all the stories about the indoor fireworks and Jose Mourinho describing him as an 'unmanageable' player.
"I could see that, in the right mood, he was a quality footballer but the rest of his career seemed like a spectacular waste of talent. That was my opinion of Balotelli."
Liverpool are paying the price for Rodgers' "massive gamble" in the transfer market this summer, according to former Anfield director of football Damien Comolli.