Romelu Lukaku suffered an injury in Chelsea's Champions League encounter with Malmo and lasted just 23 minutes before Thomas Tuchel was forced to take him off.
The Belgian striker was on the receiving end of a dreadful challenge by Lasse Nielsen to win a penalty for his side, which Jorginho converted to double the Blues' lead after Andreas Christensen's opener.
Lukaku was clearly struggling in the aftermath of the clumsy tackle, which left him clutching his lower leg, and Tuchel chose to send on Kai Havertz in his place rather than risk worsening the issue.
To make matters worse for the Chelsea manager, he then witnessed Lukaku's attacking colleague Timo Werner pull up with a suspected hamstring complaint shortly before half-time, with Callum Hudson-Odoi sent on in his place.
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Romelu Lukaku was brought down in the box by Lasse Nielsen
Lukaku's injury comes a matter of days after Tuchel voiced concerns over the 28-year-old's heavy workload for club and country.
Discussing the £97.5million summer signing, the German said: "We are in the process of adapting to each other and in my opinion, I feel Romelu is being overplayed.
"I think he played too many competitions over the summer, with his national team and now the Nations League.
"He is a fantastic athlete and such a competitive guy that he wants to win these things.
"I know how much he wanted to have a good outcome for a European Championship with Belgium and now again in the Nations League, which was a huge match for him personally as it means a lot to him to play for his country, so he takes it really seriously.
"If that doesn't work well, he always takes it on his shoulders, thinks about it and reflects and I feel he is mentally tired. Not hugely so that we have a concern, but for me he is not fully enjoying it without having second thoughts.
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"It is difficult to judge. Does he really need a break, or is it better to keep him on the pitch? The next national break is coming but this is what I feel particularly for him, and some other players too."
Despite Tuchel suggesting he could rest Lukaku for the visit of Swedish minnows Malmo, the former Everton and Manchester United star was handed another start on Wednesday night.
He was searching to end a goal drought which extends back to the Champions League victory over Zenit St Petersburg on 14 September.