The Blues are believed to be pursuing a move to sign Spain Under-19 international Marc Guiu from Barcelona this summer.
However, even if they managed to secure the 18-year-old's signature, Chelsea are still expected to recruit another striker to provide competition to Nicolas Jackson.
The Blues have been linked with a variety of targets, including Lille marksman Jonathan David and Hoffenheim forward Maximilian Beier.
Aston Villa's Jhon Duran is another name that has been mentioned, while they have also had a bid rejected for Atletico Madrid's Samu Omorodion.
Chelsea enquire over Isak deal
With Chelsea casting their net far and wide, it appears their striker search has now taken them up to the North East of England.
According to the Daily Mail, the Blues have made an enquiry over a potential deal to sign Isak from Newcastle this summer.
The report claims that talks have taken place between the two clubs over a possible move for the Sweden international.
However, Chelsea have been made aware they will need to break their transfer record to prise Isak away from St James' Park.
The Blues broke their transfer record last summer as they splashed out £115m to sign midfielder Moises Caicedo from Brighton & Hove Albion.
Could Chelsea make statement signing?
If Chelsea could strike an unlikely deal, it would represent a significant statement ahead of Enzo Maresca's first season in the Stamford Bridge dugout.
Isak has proven to be an accomplished Premier League striker since joining Newcastle from Real Sociedad in the summer of 2022.
The 24-year-old netted 10 times in 22 Premier League appearances in his first season as a Newcastle player, before he upped the ante to rack up 21 goals in 30 top-flight matches during the 2023-24 campaign.
As a result of his impressive tally, Isak finished last season in third place in the Premier League scoring charts - behind Chelsea's Cole Palmer and Manchester City's Erling Haaland.
Newcastle are still determined to keep hold of Isak despite concerns they could sell key players to meet the Premier League's Profit and Sustainability Rules.
The Magpies are seemingly keen to extend the striker's current contract which runs until June 2028, but they are yet to reach an agreement over a new deal.