article_snippet: However,  Raphael Varane has grown frustrated this year with Carlo Ancelotti preferring Pepe and Sergio Ramos as Jose Mourinho centre-back pairing when fit.
article_snippet: Appearances: Lens 23/Goals 2; .
article_snippet: The 21-year-old has grown frustrated with Carlo Ancelotti preferring Pepe and Sergio Ramos as his centre-back pairing when fit Pepe and Sergio Ramos Sergio
article_snippet: Mourinho has concerns about the centre of Mourinho defence.
article_snippet: Gary Cahill has sometimes looked uneasy against European opposition while John Terry is 34.
article_snippet: Kurt Zouma has done well this season but is still inexperienced and  Raphael Varane is already an assured performer at international level.
article_snippet: John Terry John Terry will be given a new one year contract while Branislav Ivanovic, who is 31, has 16 months left on contract.
article_snippet: The Blues also have Andreas Christensen and Tomas Kalas in reserve but both lack big game experience.
article_snippet: Mourinho has concerns over John Terry and Gary Cahill in the centre of his defence his defence .
article_snippet: Kurt Zouma, aged 20, has forced Mourinho way into the first team this season .