Stamford Bridge side keen on Schalke centre-back.
German source Bild Chelsea are one of two Premier League sides pursuing highly rated Schalke defender Kyriakos Papadpopoulos.
The Greek international is said to have a €22.5m (£19m) release clause which both Chelsea and Liverpool are seriously considering triggering this summer.
Chelsea would appear to be the favourites to win any battle between the two English sides and Roman Abramovich may well be keen on bringing in another defensive option given the limited role that experienced skipper John Terry now plays in the Blues first team.
Papadopoulos is into his third season at the Gelsenkirchen side and has been a first team regular ever since arriving from Olympiakos but has missed much of the current campaign with a knee injury.
Papadopoulos is a solid no-nonsense performer who rarely makes mistakes and is also very handy at popping up with occasional goals and is a regular in the Greek national team.
The 21 year old may well jump at the chance of a move to Stamford Bridge and may be all the more inclined to leave Schalke if they fail to secure a Champions League spot. His side currently sits in fourth spot but are just ahead of Freiburg and Eintracht Frankfurt with just one Bundesliga game left to play.
Though Chelsea can call upon the likes of Gary Cahill, David Luiz and Branislav Ivanovic to fill central defensive spots they may well see Papadopoulos as a great asset for the long term.