After a successful spell with Santos, Giovanni moved to the Spanish club Barcelona in 1996. He was a first team regular for two seasons and scored 18 goals overall. Barcelona fans still remember him for his ability to score game-winning goals against rivals Real Madrid. In his first year with Barcelona he won the 1996–97 UEFA Cup Winners' Cup under manager Bobby Robson. When Louis van Gaal took the lead in his third year at the club, however, he eventually fell out of favour with the Dutch manager, along with compatriot Sonny Anderson, despite scoring crucial goals in games such as the 1997 UEFA Super Cup second leg game against Borussia Dortmund. Due to his poor relationship with van Gaal, Giovanni left for Greek club Olympiacos in the summer of 1999, for a record transfer fee of £10,800,000. Later on in his career, he caused some controversy, by referring to van Gaal as a Hitler for Brazilians, and an egomaniac.