Chelsea boss Thomas Tuchel insisted football is a team sport as he hit back at persistent questions on out-of-form striker Romelu Lukaku at his post-match news conference, following Chelsea’s 2-0 win over Lille in their Uefa Champions League round-of-16 first-leg clash.

Tuchel’s side took control of the tie thanks to Havertz’s first-half header and Christian Pulisic’s clinical finish after the break at Stamford Bridge.

But Chelsea’s sixth successive win in all competitions was more a referendum on their Lukaku conundrum than an indication of their chances of retaining the trophy.

Lukaku has scored just 10 goals since a club-record £97-million ($131m) move from Inter Milan last year that was expected to launch a period of sustained dominance for Chelsea.

He touched the ball only seven times in Saturday’s 1-0 win at Crystal Palace, the lowest total by a Premier League player since 2003-04.

Despite being infuriated in December by Lukaku’s public questioning of the way he was being used, Tuchel had appeared to back him on Monday, insisting his problems were no laughing matter.

But, tellingly, Chelsea were more potent in Lukaku’s absence and it remains to be seen if Tuchel will trust his beleaguered star in the League Cup final against Liverpool on Sunday.

At least Tuchel knows Chelsea have the ammunition to damage opponents while their supposed leading man labours.

“For Kai, I’m very pleased. He’s been very strong for several weeks now. He really stepped up. The work rate is immense. The areas of the pitch he covers for us is very good. He is never shy of defending,” Tuchel said.

“Romelu struggled in the last game to deliver. Not only mentally tired, but physically, which I can understand. It was the moment to take a step back.

“Today we went with other players. For Sunday, we have four days to recover and decide who plays.”

As questions over the striker persisted the German coach hit back saying that there were nine other players who didn’t play and that football is considered a team sport.

Watch the full post-match conference here: