Lukaku's form not a laughing matter for Tuchel

Last Saturday's figure is the fewest number of touches registered by any player who completed the 90 minutes since such data was first recorded in 2003.

Tuchel was grilled on how to get the best from the Belgian, who the Blues signed for a club record fee in August, ahead of his side's return to Champions League action against Lille in the last 16. Chelsea won the Champions League without Lukaku last season, but his signing was made with the intention of challenging for the Premier League title.

The 28-year-old has just five Premier League goals so far in his second spell at Stamford Bridge, three of which came in his first three appearances. The seeming incompatibility between Lukaku and the rest of his teammates was summed up by the scarcity of his involvement at Selhurst Park as Chelsea escaped with a late win thanks to Hakim Ziyech's strike. "It's not what we want and not what Romelu wants but it's not the time to laugh about him and make jokes," Tuchel said. "He is in the spotlight and we will protect him because he's our player."

Tuchel defended accusations that it is his preferred 3-4-3 system that Lukaku is failing to adapt to. Lukaku was dropped for a vital clash against Liverpool on January 2 after voicing his frustrations as Tuchel's style of play in a December interview with Sky Italia. However, the German coach pointed to the struggles of other strikers at Chelsea in recent seasons prior to his arrival such as Fernando Torres, Alvaro Morata and Timo Werner to prove his point that Lukaku is not an isolated case.

"There's even a history of strikers struggling a little bit at Chelsea so it's not the easiest place in the world for strikers but I don't know exactly why it's like this," he added. "We had many games throughout the year together where we created many chances but struggled a bit in the conversion. Now at the moment it's a time where we struggle to create too many big chances for our strikers and I think this is a normal period in a long season. "We are well aware of it but like most of the time in football, there's not one way to solve a problem. It's a very complex sport and we try to keep on playing with belief in the team effort."

Even despite Lukaku's struggles, Chelsea are strong favourites to reach the last eight of the Champions League against the French champions. Lille sit 11th in Ligue 1, having failed to hit the heights of last season when they shocked Paris Saint-Germain to claim the title. Chelsea have fallen 13 points behind Manchester City in the battle for the Premier League, but have a perfect record of reaching four finals in knockout competitions under Tuchel.

"We should not think too much of how others could see us as the favourites against Lille," said Tuchel. "We are confident of having a good performance because we deliver on a high level in knockout matches, cup matches and Champions League matches."