Chelsea have now joined the race to sign a "hugely impressive" £70m forward, who recently broke a Champions League record.
Blues' winning streak ended by Sunderland
After winning four games on the spin in all competitions, Chelsea fans could be forgiven for expecting a comfortable victory at home against newly-promoted Sunderland, but their winning streak was brought to an abrupt end.
Chemsdine Talbi's stoppage-time winner secured all three points for the visitors, with the Blues hardly laying a glove on their opponents, recording an xG of just 0.90 throughout the match, which will no doubt be a concern for Enzo Maresca.
It was a very poor performance from the hosts, and perhaps the only slight positive was Alejandro Garnacho's performance, with the summer signing scoring his first goal since arriving from Manchester United.
It is still early days, but Garnacho will now be hoping he can kick on and silence the doubters, with journalist Ollie Holt not convinced the winger's move to Stamford Bridge will pan out.
According to a report from Caught Offside, Chelsea have also joined the race for another young forward, having sent scouts to watch Bayern Munich forward Lennart Karl in action, but a deal is expected to be on the expensive side.
Indeed, Bayern value their break-out youngster at around €70m - €80m (£61m - £70m), which means the west Londoners may need to shell out a huge fee to tempt the German club into a sale.
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Having recently smashed the previous record to become Bayern's youngest-ever Champions League goalscorer, a number of top clubs have joined the race for Karl, with Arsenal and Manchester City also named as potential suitors.
"Hugely impressive" Karl could be future star
It is a very promising sign that the 17-year-old has managed to force his way into Vincent Kompany's plans at such a young age, featuring six times in the Bundesliga this season, during which time he has chipped in with two goal contributions.
Having also gotten off the mark in the Champions League, the teenager has proven he could be a future star, but there are doubts over whether he is the type of signing that Chelsea need at this stage.
The Blues added Jamie Gittens and Garnacho to their ranks this summer, so it is questionable whether they need to bring in another young winger, with Paul Merson recently emphasizing that a lack of experience is a real issue.
Merson said: "The team is too young. The oldest player there is 23, 24? When you get a young team, you’re up and down, they have wingers who are very inconsistent."
As such, rather than signing Karl, who has been described as "hugely impressive" by scout Ben Mattinson, Chelsea could do with bringing in players with more experience, instead of being so hell-bent on only signing young players.