Roberto Fabián Ayala (; born 14 April 1973), nicknamed El Ratón ("The Mouse"), is an Argentine former footballer who played as a centre back for the Argentina national football team, as well as Valencia and Real Zaragoza in Spain, Milan and Napoli in Italy, and Ferro Carril, River Plate and Racing Club in his native Argentina. Regarded as one of the best central defenders of his generation, he stood out for his leadership and ability in the air throughout his career in spite of his small stature as a centre back. Ayala captained Argentina in a record 63 matches. He played in three FIFA World Cups and made a total of 115 international appearances, behind only Javier Mascherano, Javier Zanetti and Lionel Messi in terms of international appearances. Club career Early career in Argentina Ayala began his career in his native Argentina, playing for Ferro Carril Oeste. After three seasons, he moved to River Plate where his good form attracted the attention of clubs in Europe. Move to Europe Parma, Napoli and Milan Italian side Parma brought the Argentine defender to Europe. However, the club, having already used their quota of three non-EU players, loaned him to Napoli, who purchased 50% of his rights on a co-ownership deal. Ayala was bought by Milan at the end of the 1997–98 season and played there for two seasons until Valencia purchased him for £6.25 million. Valencia After signing with Valencia in the summer of 2000, Ayala made 275 appearances during a seven-year spell at the club. On 24 September 2000, Ayala made his debut for Valencia in a 3–0 La Liga win over Numancia. He soon established himself as a first choice central defender for Los Che and started alongside compatriot Mauricio Pellegrino in the 2001 UEFA Champions League final, where Valencia lost 5–4 to Bayern Munich after a penalty shootout. He was later named best defender for the 2000–01 tournament. The following season, Ayala was part of the Valencia team that won the 2001–02 La Liga title. He scored the opening goal of a 2–0 defeat of Málaga which secured the championship on 5 May 2002. In 2003–04, Valencia again won the La Liga title and beat Marseille 2–0 in Gothenburg to win the UEFA Cup. During the 2004–05 season, injuries kept Ayala from much of the La Liga campaign as well as the UEFA Super Cup victory over Porto. During