Thomas Tuchel is unsure whether Romelu Lukaku will return for Chelsea's Champions League showdown with Juventus, while Kai Havertz could miss out entirely.

Record signing Lukaku has been out for a month due to an ankle injury but is closing in on a comeback.

The Belgium striker was able to resume training last week, but Blues manager Tuchel will not rush him back into the side at Stamford Bridge on Tuesday.

While Lukaku's involvement appears undecided, Havertz seems unlikely to feature after suffering a hamstring injury against Leicester City.

Jorginho will be available after coming off with a cramp in the win over the Foxes as the second-placed holders look for a win that would put them level on 12 points with the Group H leaders.

Asked about the possibility of Lukaku returning, Tuchel said: "Not sure yet. He seemed okay in training yesterday [Sunday], we will see about the reaction."

"He has an appointment with the doctors and physios. Maybe we can bring 20 players to the squad. The last minutes would be the absolute maximum."

"Jorginho is absolutely okay. Kai had a hamstring problem so we took him off and we have some doubts with him."

Chelsea are unbeaten in nine matches – winning seven and edging a penalty shootout – since losing 1-0 to the Bianconeri in September.

It has been reported that owner Roman Abramovich could be in attendance for the battle between the top two, but Tuchel says that will not give his side extra motivation to put on a show.

The German said: "Our show is the basics. We give our very best if the owner is here or if he is not here. He will watch us closely anyway if he isn't here."

"We put a show on a daily basis and that is with hard work to make him happy and all our supporters who are in the stadium tomorrow. We need everyone full-on and ourselves to be at the top level."

The London club have only won one of their past 10 Champions League encounters with Italian sides.

Tuchel says Chelsea will not shoot themselves in the foot by taking a gung-ho approach to trying to qualify as group winners.

"We will not risk our qualification and go all-in if the situation is like this, but we will try everything to win the game and the group and to do this, we have to win the game," said the former Paris Saint-Germain and Borussia Dortmund boss.