Thomas 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. The holders will expect to complete their progress to the quarter-finals when they travel to France for the second leg on March 16. 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 move from Inter Milan last year that was expected to launch a period of sustained dominance for Chelsea. He touched the ball just 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. Asked about his decision to drop Lukaku, Tuchel said: "He looked a little exhausted and you have to consider that he's played a lot."

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.

Chelsea's Ben Chilwell, Reece James and Callum Hudson-Odoi paraded the Club World Cup around the pitch just before kick-off. However, that victory in Abu Dhabi will be only a footnote in the story of Chelsea's season if they don't mount a strong finish to an inconsistent campaign. This was a step in the right direction and Havertz didn't take long to get involved.

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