Now Thomas Tuchel claims the club record £97.5million signing is mentally and physically tired before the clocks have even gone back.
Whatever the reason, something is not right with the striker who blasted Inter Milan to the Serie A title last season and was considered the final piece of the jigsaw when returning to Chelsea in the summer.
A run of six games without a goal is his longest barren spell since his miserable final season at Manchester United, which saw him fail to score in his final eight appearances.
His present situation is nothing like as desperate as that, but Lukaku’s flying start has been brought down to earth. Against Brentford on Saturday, he was taken off after 76 minutes having failed to register a single shot on target and only one of any description during the match.
Those statistics raise questions about the quality of service being delivered to a man who scored 64 goals in 95 appearances for Inter. It also places the spotlight on Tuchel’s system, which continues to prioritise a stubborn rearguard over a free-flowing attack.
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