Jose Mourinho failed with summer bids for both players and has since seen his Blues defence struggle for form in a big way and as such it’s perhaps no surprise that the West London side would make plans to bolster their back-line.
Moves of £38m and £30m for Stones and Marquinho respectively were turned down during the last transfer window and it will take nearer to £40m to bring in either of the two players, such is their standing and potential.
Stones is now a regular in the England national team set-up and a player Everton may struggle to keep hold of in the long-term but Mourinho may find it easier to lure Marquinhos in January.
The 21-year-old, who moved to the Parc des Princes from AS Roma in 2013, has started just four of PSG’s nine Ligue 1 fixtures this season with Laurent Blanc opting to use David Luiz and Thiago Silva as his first-choice defensive options.
Chelsea have conceded 17 goals in Premier League action this season, only Sunderland have let in more, with Jose Mourinho opting more recently to use Gary Cahill and Kurt Zouma as his central defensive partnership, with captain John Terry having been dropped on a number of occasions.