Brendan Rodgers was always convinced Raheem Sterling would become "a world-class operator" after helping to feed his hunger during the early stages of his career at Liverpool.
Following his appointment as Reds boss in June 2012, Rodgers helped a then 17-year-old Sterling blossom before he was sold for £44million three years later to Manchester City.
The paths of Rodgers and Sterling again cross on Saturday when second-placed Leicester take on third-placed City at the Etihad Stadium, with both sides needing victory to close the gap to leaders Liverpool while they are in action in the Club World Cup.
Appreciating the player Sterling has become, Rodgers said: "Raheem was always a joy to work with. He was a very young player who had clear ambitions, but he backed that up with his work.
"When we put him into the team he played with such intensity, such drive and quality, and there were lots of positions he played in for me because he was so versatile, such an incredible young footballer.
"But he always had the hunger to learn, and when he left to go to Manchester City, you could see that hunger to improve."
Under City boss Pep Guardiola, Rodgers recognises Sterling has now become one of the game's top stars.
"With Pep's coaching he has developed into a consistently world-class operator, and he will believe himself there is still a lot more to come," added Rodgers.
"Off the field, he was a great boy, and he always stood up for what he believed in as well, off the pitch and on it.
"It's been fantastic to see his development from a young player at 17 into a world-class talent.
"And people will tell you he is still the same, a humble young guy who is not frightened to work, and has this amazing talent that he works at."
With the Foxes currently 10 points adrift of Liverpool, the clash with City is one Rodgers' side effectively cannot lose ahead of their Boxing Day battle with Jurgen Klopp's pacesetters.
"It's one where we can only think about ourselves because we can't forecast what the other teams are going to do," assessed Rodgers.
"We're approaching the midway part of the season and we're happy with where we're at, but we still have goals and objectives to achieve.
"We're in a position in which no-one expected us to be, but the growth of the team and the confidence they're gaining from how we're working has allowed them to be in the position we're in.
"We have to consistently work on that, and let's see where it takes us."
As to whether he feels City are good enough to win the title, he added: "We will do out best. There are clubs much bigger than ourselves, but we love the challenge of being in the competition, and we're comfortable with our position.
"But we're not getting carried away because it's a very tough league with some amazing teams. Over the first part of the season we've showed some great consistency, and we will look to take that into the second part."
