Chelsea are looking at potentially signing Kylian Mbappe from PSG this summer after he was put up for sale by the French champions and left out of their pre-season tour squad
The fact Mbappe has gone on to become one of the world's best footballers, however, will undoubtedly hurt those who are still at Stamford Bridge who were there back then.
Now though, Chelsea could rectify that error, by signing Mbappe at the age of 24. Mbappe is set to leave Paris Saint-Germain, either this year or next year on a free, and the Blues are making a move to sign him.
Mbappe has just one year left on his contract at PSG and has no intention of signing a new one. PSG on the other hand have no intention of letting him leave on a free next summer, so have put him up for sale and omitted him from their squad for their pre-season tour of Japan and South Korea.
PSG president Nasser El-Khelaifi said last month: "My position is very clear. I don't want to repeat it every time: if Kylian wants to stay, we want him to stay. But he needs to sign a new contract.
"We don't want to lose the best player in the world for free. We can't do that. This is a French club."
He said: "I played up front, but I don't think I scored. It was great – it was my first experience abroad and a chance for me to see what the game was like in England."
Former Chelsea scout Daniel Boga recalled the moment in an interview with Goal in 2018. The Blues wanted Mbappe to come back for a second week, as they were hesitant to sign him because "defensively he wasn't there". That second week trial was not accepted.
Boga said: "I remember what the mother (Fayza) said to this day. She said to me, 'Listen, my boy won't be coming back. If they want him they have to take him now, or in five years' time they will be coming back to buy him for €50million (£43.3million)'."
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