Jose Mourinho says Mohamed Salah was "lonely, naive and physically fragile" during his time at Chelsea.
The Egyptian made just 13 appearances for Chelsea after arriving from Basel in 2014 and was quickly shipped to Italy for spells with Fiorentina and Roma.
Salah has since become a star at Anfield and Mourinho believes the experiences in Italy helped him develop into a top player.
"He arrived at Chelsea coming from Basel," he told beIN Sports. "He was a lonely boy, a naive boy and physically fragile.
"Then he goes to Italy and has the experience at Fiorentina and Roma.
"When he comes back to England he has completely adapted to the high level of European football with more understanding of the game and physically much stronger, much more confident.
"When the player is obviously talented, years can change the player for the better."