Age and injuries have finally started to catch up with Roberto Ayala but he remains one of the finest defenders in the world. The vastly experienced centre-back had spells with River Plate, Napoli and AC Milan before enjoying the most successful period of his club career following his move to Valencia in 2000. He was a key figure as the club won the Primera Liga title in 2001-02 and 2003-04, as well as the 2004 UEFA Cup. Ayala, who is renowned for his aerial prowess and unrivalled ability to read the game, was a member of the Argentina team that won gold at the Athens Olympics, but struggled to make an impact during the country's disappointing 1998 and 2002 World Cup finals campaigns.