Those issues have now become a thing of the past with Sterling, who joined City in 2015, improving markedly under the guidance of Pep Guardiola at the Etihad Stadium, getting better year on year.

Already this season he has netted 19 goals across 26 appearances for club and country.

Sterling said: "It's all about mentality: mentality, maturity and growing up. I think now I'm living for football. I'm obsessed with football, obsessed with scoring goals, obsessed with recovering quicker, and obsessed with improving myself.

"You have every facility here so you have to use it to the best of your advantage to try and be the best you can be.

"I was decisive but I wasn't 100 per cent committed, I wasn't 100 per cent living the way I should be living to be a professional footballer and that would give me an edge on a match day. I realised that and changed it.

"You see the improvements on the pitch and so that's why you continue to do it, because you see how you feel on the field and what your output is, you look at what your numbers are doing.

"It's a good thing and as a professional you have to learn, take it in your stride and keep learning. That's all I do."

Sterling, who has won two Premier League titles with City, also feels he has been spurred on by the competition for places in the squad.

He said: "We challenge for our positions in the team and that's what I've done from day one.

"With the quality of players we have in each position, we have to be hungry and ready. There's always somebody who can take your position. I enjoy that. It's great to have competition to keep you on your toes."