Paul Merson believes Chelsea have sold themselves short after failing to sign a world-class centre-back in the transfer window. The former Arsenal man turned Sky Sports pundit thinks the Blues have done some smart business in signing Pedro, but feels they needed a top draw central defender this summer. They did sign Papy Djilobodji from Nantes, but Merson is not convinced the 27-year-old will see much game time at Stamford Bridge. In other news, Nathaniel Chalobah has become the 33rd Chelsea player to go out on loan this season after his move to Napoli was confirmed. The 20-year-old has had previous spells in the Championship and Premier League and will be able to test himself in Serie 'A' and the Europa League with his new club. And finally, Chelsea were prepared to smash the British transfer record in order to secure the services of Paul Pogba, according to the Independent.