Since arriving in Naples in 2020, the forward has proceeded to enjoy a legendary stint, scoring 65 goals and contributing 16 assists from 112 appearances in all competitions.
A large chunk of those strikes came during Napoli's Serie A title-winning campaign in 2022-23, ending a wait of more than three decades to lift the trophy.
However, with a different manager at the helm and already eight points adrift of leaders Inter Milan in the standings, there is a different mood at Stadio Diego Armando Maradona this season.
That includes the situation involving Osimhen who, while still making an impact, has faced constant speculation regarding his future and was on the receiving end of two offensive posts from the club's social media team in recent times.
With just over 19 months remaining on his contract, a decision will soon need to be made regarding everyone's next move, there seemingly being an impasse over any progression.
At a time when Osimhen is said to have little interest in a renewal, Napoli president Aurelio De Laurentiis is prepared to play hardball over a sale, insistent on making a profit on the €80m that they shelled out more than three years ago.
The likes of Chelsea and Arsenal - alleged admirers of the 24-year-old - have always been conscious that it would take in excess of that fee to sign Osimhen in January or next summer.
Nevertheless, according to Il Mattino, De Laurentiis is currently insisting on receiving €150m (£130.06m) for his star man.
How any of his suitors react to that stance remain to be seen with it having recently been alleged that Chelsea plan to make a move in January.
Co-owners Todd Boehly and Clearlake Capital are not in a position where they can afford that fee due to their FFP restrictions, unless they make a number of sales to offset that figure.
From Arsenal's perspective, that stance would automatically rule them out, and it has already been suggested that they are priortising other positions at the start of 2024.
Despite De Laurentiis reportedly wanting to demand what would be one of the biggest fees in world transfer history, Napoli's position will significantly weaken if they reach next summer without Osimhen penning a renewal.