Chelsea head coach Maurizio Sarri believes Callum Hudson-Odoi is not yet ready for the Premier League despite impressing against PAOK on Thursday.
Hudson-Odoi, 18, scored his first goal for the club as Chelsea cruised to a 4-0 victory in the Europa League, securing top spot in Group L.
But Sarri feels the teenage forward must improve before getting his chance in the Premier League.
"I don't know if he is able for the Premier League at 18, especially in a big team," he told a news conference.
"If he's already ready now to make a difference in the team like Chelsea, he would be the best player in Europe in two years."
2 - Chelsea are just the second English side to win their opening five games of a Europa League group stage campaign, after Spurs in 2013-14. Cruise. November 29, 2018
Chelsea ended a two-game winless run with their victory over PAOK, who were reduced to 10 men in the seventh minute when Yevhen Khacheridi was sent off.
Olivier Giroud scored a first-half brace and Alvaro Morata was also on the scoresheet in a boost for Chelsea.
But Sarri said the win over the Greek outfit made little difference to his plans for Sunday, when his side host Fulham.
"In the last match, the problem was the team, not one or two players," he said.
"So I think that if there were two different players, it would have been the same. The big problem was the team."
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