According to the Evening Standard, Chelsea is keen to make Gvardiol their No1 transfer target to replace Cesar Azpilicueta, who is reportedly set to join Barcelona this summer.
Gvardiol has been linked with a move to Chelsea throughout the summer and the Premier League giants are keen to sign three central defenders this transfer window.
The 20-year-old featured 46 times for RB Leipzig last season, helping the German club win the DFB Pokal and qualify for the UEFA Champions League.
Chelsea has already completed a deal for Kalidou Kouliably from Napoli.
Chelsea manager, Thomas Tuchel, wanted to bring in Manchester City’s Nathan Ake but the Citizens were not willing to sell so attention could turn to Gvardiol.