"He did very well, he is improving in the last month", he told BT Sport.
On his continental outing in Ukraine, Loftus-Cheek said: "I really enjoyed it, it was my first 90 in a while.
Football news - Arsenal draw Napoli in quarter-final, Chelsea to face Slavia Prague
So, for me, it will be very hard to play against them in Naples".
"Physically, technically and tactically he is improving".
Arsenal and Chelsea, however, might need a path into the top-tier competition next season by taking the place reserved for the Europa League victor. "He can become one of the best midfielders not only in England but in Europe". "We played a wonderful first half and managed the game in the second half".More news: Theresa May in final Brexit push
Elsewhere, Napoli wrapped up a 4-3 aggregate victory over last season's semi-finalists Salzburg despite a 3-1 second-leg loss in Austria.
Carlo Ancelotti has missed the trickery and talent of Insigne on a few occasions this season, with the 27-year-old having scored nine goals and setting up a further six in Serie A so far this term. "First of all, because it means we are in the final and I am happy with that", Sarri said.
Maurizio Sarri would surely love to win a trophy during his first campaign in charge at Stamford Bridge and his path to the final has now been mapped out.More news: Vietnamese woman loses bid for release
Manchester United face Wolves in the quarter-finals so the Blues have an excellent opportunity to put the pressure on their immediate rivals.
The victor of the quarter-final between Napoli and Arsenal will certainly be favourite to make the final, both of which are capable of causing a serious threat to the Blues.
"In fact I think he's been very good for Chelsea since he's been at the club, possibly underrated in many respects but proving it again in the Europa League that he can score goals".More news: Multiple deaths in shooting at Mosque