Callum Hudson-Odoi has been told he will not be sold by Chelsea before Thursday’s transfer deadline – or in the summer.
The 18-year-old is out of contract in June 2020 and has been linked with a £35million move to Bayern Munich.
Chelsea on Monday reportedly turned down a transfer request from Hudson-Odoi, with head coach Maurizio Sarri reiterating to the club’s stance on Tuesday.
Sarri said: “On the pitch he’s doing very well. I’m really very happy with him. I’m not very happy with the situation, but I know very well that every big team here in England has the same problem.
“It’s not easy to keep these young players. He is of course one of the best 18-year-old players in Europe, so it’s very, very difficult. The club told me he’s out of the market for sure and probably he will be out of the market in July.”
Hudson-Odoi scored his second Chelsea goal on his sixth start of the season in Sunday’s FA Cup fourth-round win over Sheffield Wednesday.
He is yet to start in the Premier League and has made just three substitute appearances in the top flight, the first coming on Boxing Day at Watford.
Speaking ahead of Wednesday’s Premier League clash at Bournemouth, Sarri added: “He’s improving. I think he’ll be the future of our club. He will be the future of English football.”
For Hudson-Odoi to stay into the 2019-20 season it would seem Chelsea must persuade him to sign a new contract.
Sarri insisted that is not his remit and the 60-year-old Italian would make no guarantees to Hudson-Odoi on match time.
Sarri said: “I cannot do anything, as you know very well. If I have the power to sign a new contract, I can do everything.
“It’s impossible to promise him that he will play every match, because it depends on the situation.”
Sarri had hoped to make two signings this month. Only Gonzalo Higuain has arrived so far, on loan from Juventus, and the head coach is keen to recruit a replacement for Cesc Fabregas, who has left for Monaco.
Sarri added: “I thought for us it was important to have two players. One has arrived. I am waiting for the other.
“If he will arrive, I will be very happy, otherwise I have to work with these players. It’s not a big problem for me.”
Ethan Ampadu was deployed in the central midfield position where Jorginho is first choice, but the 18-year-old Wales international fared poorly, Sarri said.
Higuain made his debut against Wednesday, afterwards telling Sarri “they are so aggressive”. Sarri told him it was “normal”.
Sarri could offer no clarification on the futures of midfielder Danny Drinkwater or defender Gary Cahill, who are both out of favour.