Chelsea are targeting RB Leipzig striker Christopher Nkunku AND Josko Gvardiol.
The Sun says the Blues made a £80m bid for his team-mate Gvardiol during the last transfer window but were told to wait 12 months to clinch a deal.
Nkunku, 24, will cost around £53m and underwent a medical in Germany last month as part of the future arrangements.
Chelsea boss Graham Potter and chairman Todd Boehly are mindful that experienced centre-half Thiago Silva is now 38 and that this area of the team requires strengthening.
Gvardiol, 20, is being earmarked by Chelsea as the long-term solution to replace Silva.
The Croatian has opened the door to a move to Stamford Bridge as early as January, despite signing a new five-year deal with the club last month.