The Sun says Spurs beat Chelsea, Manchester City and Inter Milan to the Mexican winger. Giovani, 19, was swayed after meeting White Hart Lane chiefs in London back in January.
Inter and City were last night desperately trying to persuade agent Pini Zahavi to get the player to change his mind.
Spurs' swoop has stunned Chelsea, who made two failed raids for Giovani after tracking his development for four years.
Barca offered Gio the chance to move on loan but he has grown disillusioned with the Nou Camp.