London - Belgian star Eden Hazard's recent struggles with injury is giving Chelsea manager Maurizio Sarri cause for concern the Italian admitted on Wednesday.
The 27-year-old playmaker -- who played a pivotal role in Belgium finishing a best ever third in the World Cup in Russia earlier this year -- is out of the Europa League match with Greek outfit PAOK on Thursday with an ankle problem.
Chelsea are already guaranteed a place in the knockout stages -- they need a point to win Group L with one match to go -- but Sarri will want Hazard fighting fit come Sunday's Premier League match with struggling Fulham.
"I am worried because 25 days ago he had a back injury," said Sarri at his eve of match press conference.
"Now an ankle. He has lost a lot of training.
"It's normal at the moment he isn't at the top of his physical condition."
Sarri has other concerns too about another key midfielder N'golo Kante but this is with regard to his positional play.
The Italian pointed the finger at the French World Cup winner for being partly to blame for his 18-game unbeaten start at the club ended with the 3-1 defeat by Tottenham Hotspur last Sunday.
"I want to play as a centre midfielder with a very technical player. For me the centre midfielder is Jorginho or (Cesc) Fabregas," said Sarri.
"I don't want Kante in this position. Kante in the last match wanted to solve the match after the first 15 minutes, but in the wrong way.
"He lost the position, he attacked too much the other box. And I think this one is not one of the best characteristics of Kante."
Kante won two Premier League titles, with Leicester and Chelsea, playing in central midfield, but has been deployed out of position on the right to accommodate Jorginho in Sarri's chosen style.
Sarri said the 27-year-old -- who signed a new five-year contract last week -- should acknowledge his responsibilities lie elsewhere.
"Kante has to stay near to Jorginho, especially when the ball is on the other side," said Sarri.
"It depends on the action. If the ball is on the left, we have (Marcos) Alonso, (Eden) Hazard, (Mateo) Kovacic, (Ross) Barkley, so in that situation he has to stay very close to Jorginho."