In 2002 Antonio became the test driver for Williams, and after some impressive testing performances he was signed by Jaguar for a 2003 race seat.
Debut & Jaguar (2003)
Midway through 2003 after a string of poor results (his best of 11 rounds, a 9th in Austria) he was dropped from the Jaguar team, being replaced by Justin Wilson.
In 2004 he returned to Williams as their test driver. He stood in for the injured Ralph Schumacher for the German, Hungarian, Belgian and Italian Grands Prix, gaining three 7th places and a DNF.
He also stood in for the injured Nick Heidfeld in 2005, competing in the Italian, Belgian, Brazillian, Japanese and Chinese Grands Prix. He scored 2 points (7th) in the first of these, however in the Belgian Grand Prix he crashed into Juan Pablo Montoya whilst trying to un-lap himself, he was fined $8,000 by the FIA.
Since his stint in F1, Antonio has raced in Champ Cars, GP2, and Brazilian stock cars.