Chelsea scouts left the Napoli vs Monza game unimpressed by Victor Osimhen on Sunday.
Osimhen fired blanks as newly crowned Serie A champions lost 2-0.
This could mean that the Blues might take a step back from the race to sign the forward in the summer, with Manchester United being deemed the frontrunners to land the player, according to Il Mattino.
The Red Devils were in touch with Napoli president Aurelio de Laurentiis over a possible Osimhen transfer, but a deal did not materialise. Other than Chelsea and Manchester United, Newcastle, Paris Saint-Germain and Real Madrid are also keen on signing the player.
The 24-year-old striker is currently leading the race to win the Golden Boot in Serie A. He has netted 23 times thus far in 29 appearances for Napoli this season and played a crucial role in the club winning their third Serie A title.