In August 2002, Santos agreed to join English Premier League club Charlton Athletic.

But he was denied a work permit by the Home Office because he had not made the minimum number of national team appearances required for players from outside the European Union and returned to Shimizu for the remainder of the season.

He made his first appearance for Japan national team on 21 March 2002, against Ukraine,[5] and he was part of Philippe Troussier's selection for the 2002 World Cup.

Santos became the fifth naturalized Japanese citizen to play for Japan following Daishiro Yoshimura, George Yonashiro, Ruy Ramos, and Lopes.

In May 2006 he was selected in the Japan squad for the 2006 World Cup, providing an assist for Keiji Tamada in a group stage match against his former country Brazil.

[5] In 2020, Alex founded the Aruko Sports Brasil, a team that currently competes in the Campeonato Paranaense.