Chelsea are to re-sign Nemanja Matic for an eye-catching fee of around £22m, a vastly inflated price from the valuation attached to the Serbia midfielder when he was allowed to leave and join Benfica three years ago. Matic is due at Cobham on Tuesday to undertake a medical with the clubs close to agreeing a price for the 25-year-old, who has been capped nine times. The defensive midfielder had pushed for a return to Stamford Bridge after a hugely impressive spell in Lisbon, with the outlay to bring him back to England to fall well short of the £37m buy-out clause in the player's contract. He is expected to sign a contract to 2017. Yet the fee remains remarkable given Chelsea had considered Matic to be only a makeweight in the deal which brought David Luiz from Benfica in the 2011 mid-winter window, the midfielder's valuation at the time being placed at around £3m. The vast difference will be partly offset by the sale of Kevin De Bruyne to Wolfsburg for around £18m, with that transfer finally to be concluded in the next 24 hours. Matic had joined Chelsea from the Slovakian side Kosice for £1.5m in 2009 but made only three substitute appearances before he was dispatched on a season-long loan to Vitesse Arnhem. With his route into the first team at Chelsea blocked by more experienced candidates following Ramires's arrival from Benfica in 2011, and with youngsters such as Josh McEachran considered higher in the pecking order at the time, Chelsea sanctioned his departure only to watch his game flourish from afar. Physically imposing at 6ft 4in, the midfielder has developed rapidly in Portugal, impressing as a key member of Jorge Jesus's side when offered regular competitive football. An athletic runner, aggressive in the tackle and an accurate and progressive passer, Matic is entering his pomp and could make his second debut for the club in Sunday's visit of another of his mooted suitors, Manchester United. Chelsea's Branislav Ivanovic, an international team-mate, had acknowledged before May's Europa League final between the clubs that his compatriot had made considerable progress. "When he was at Chelsea you saw he has the qualities to be a top player but he needed practice," said Ivanovic. "In Portugal he has improved his defensive ways a lot and his aggressiveness. And he has great vision [going] forward." His arrival is likely to conclude the bulk of José Mourinho's incoming business in this window, scuppering the Colombia international Fredy Guarín's hopes of joining from Internazionale. Interest is retained in the young French centre-half Kurt Zouma at St-Etienne, though that transfer could be revived in the summer if no deal is struck this month.