Lukaku has struggled to make an impact at Chelsea since joining from Inter Milan for £97.5 million last year.
The 28-year-old, who has stated his desire to return to Inter in the near future, has only scored five Premier League goals this season.
Super Eagles striker could replace Lukaku at Chelsea. The former Manchester United forward is currently lower down the Chelsea pecking order, with manager Thomas Tuchel preferring Kai Havertz and Timo Werner ahead of him.
However, according to GFFN, Chelsea would be searching for a replacement if Lukaku leaves, and the two-time Champions League winners could target Osimhen.
The report added that Napoli have already contacted Gianluca Scamacca, who is seen as a replacement for Osimhen.
Osimhen has been linked to several European clubs, but Arsenal, Manchester United, and Newcastle are the forerunners.
The 23-year-old has been sensational for Napoli this season, scoring 17 goals and registering six in 29 appearances.
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