Former Manchester United and Real Madrid coach Jose Mourinho has lifted the lid on Mohamed Salah's failed stint under his leadership at Premier League side Chelsea, claiming that the Egyptian was "lonely, naive and fragile".

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Salah made the move to the Blues from Swiss outfit FC Basel in 2014, but failed to cement a spot in the club's starting XI and was limited to just 13 appearances in England's top flight before being loaned out to Fiorentina and then AS Roma, with the latter eventually making his stay a permanent one.

Mourinho, who was manager of Chelsea when Salah arrived at Stamford Bridge, has now acknowledged that the 26-year-old has grown in leaps and bounds since returning to England, and explained why he thinks the Egypt talisman struggled in London.

"He arrived at Chelsea coming from Basel," the Portuguese tactician told beIN SPORTS.

"He was a lonely boy, a naive boy and physically fragile.

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"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."

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Salah has scored 20 goals and assisted a further eight strikes in 38 appearances across all competitions for the Reds so far this season.

Do you think Salah would have had the same level of success he has today had he stayed at Chelsea? Have your say in the comments section below.