The deal is expected to be announced following the final matches in the Brazilian Serie A this weekend.
Spurs boss Harry Redknapp has tracked the 20-year-old since the summer, openly talking of his admiration for the physically imposing holding midfielder.
"We've only got three central midfield players,' said Redknapp in October. "Jamie O'Hara went, Kevin-Prince Boateng went, Didier Zokora went. Suddenly we're very, very short in there.
"So I'm looking for someone else who can play in midfield here. We've been looking at Sandro. He's just breaking into the Brazilian team from the Under-21s. He can play. He's a modern-day midfield player.
"I'd like to go and have a look myself as well and, if we do decide to do anything, it'll be up to the chairman to push it on from there."