Cape Town - Former Liverpool manager Brendan Rodgers says Raheem Sterling lost his way under Manuel Pellegrini after leaving Anfield to sign for Manchester City.
Sterling join City for a reported fee of £51 million in the 2015 off-season transfer window, having been lauded as the most promising talent in the Premier League.
However, his form and impact for England and the Citizens fell dramatically in his first season under Pellegrini.
Rodgers feels the arrival of Pep Guardiola and the lessons learnt during a difficult debut campaign has improved Sterling and he expects the winger to return to form as a world-class player.
"Obviously he left, he was a star of England and a star of Liverpool and I just think he's gone into a totally different changing room and you just need that time to settle in," the Celtic boss told the Manchester Evening News.
"He just needed to regain his identity. What he is. He's working now with a coach who is very clear in terms of how he wants to play and I think when you have that with Raheem you maximise what you get out of him.
"So he had his year of settling in and now you see him working at the level he's at and I watch him and you see him being back to where he was a few years ago, playing with big confidence, taking people on, super aggressive.
"He lost what he was which is a one v one guy who is dynamic and can take people on. He can press the game, can score goals and create goals.
"And he can work hard. I felt he drifted into being something he wasn't. But you can see him now working with a clear plan."