Thomas Tuchel believes £97m striker Romelu Lukaku's six-game goal drought has been caused by mental fatigue and being overplayed during the summer.

The Belgian international has hit a plateau after making an immediate impact following his return to Stamford Bridge in the summer, but is currently enduring a barren run in front of goal.

Chelsea host Malmo at 8pm this evening in the Champions League before welcoming Norwich City to south west London this weekend.

Tuchel has lamented the crowded calendar that is seeing footballers compete in more games over the course of a season and admits he doesn't know whether to play Lukaku in an attempt to shake off his fatigue or give him time away from the team.

"At this moment, I feel Romelu is a bit overplayed. I think he played in too many competitions over the summer, too many competitions with his country. He played the Nations League and he is a fantastic athlete and such a competitive guy that he never takes it easy.

"He wants to be out there and win. He wanted to have a good outcome for the European Championship with Belgium and now in the Nations League it was a huge match for him, it meant a lot personally to play for his country so he takes it seriously.

"If that does not work well he always puts it on his shoulders. He reflects about it and I feel him mentally tired."

Lukaku has scored 43 goals in his last 64 appearances for club and country, but has failed to find the net for Chelsea since getting a brace in their 3-0 victory over Aston Villa last month.

That record will strike fear into the heart of City fans, who are all too aware of the 'Along Come Norwich' scenario when a player or team breaks a poor record with a victory against the Canaries.

City face the daunting prospect of a trip to Stamford Bridge against the early season pacesetters after consecutive goalless draws.

Chelsea battled hard to get a 1-0 win against Brentford but their performances have seen some express doubt about their title credentials, but Tuchel believes criticism of the Blues performances are premature and unjust.

“Sometimes things can look a bit harder than it should be, but don’t forget this is the Premier League," he told PA.

“It is the toughest league in the world and there is no shame in having a tight match against Brentford and there is absolutely no shame in getting a late winner against Southampton, it is what it is.

“It is important that we are not too critical of ourselves. You have hard moments, you fight through them and be a team nobody likes to play against.

“It isn’t easy for any team in the Premier League to win any game, so maybe this is normal and we have to embrace the situation that is difficult at the moment. We are finding our ways to win the games at the moment."

NCFC extra: No panic measures over City goal struggles