Goal.com has already learned that Los Blancos have identified the Brazil international as the ideal midfield foil for Xabi Alonso, and the teenager has now admitted that he would jump at the opportunity to join the Spanish champions.
"They are one of the biggest clubs in the world," Lucas told TV Globo's 'Esporte Espetacular'. "But for now I am thinking only of Sao Paulo.
"My father went to Spain with my agent, who met the top directors, probably even Florentino Perez. There were some talks, but nothing official."
For the time being, Lucas is solely focused on nailing down his place in the Selecao's starting lineup.
"My dream now is the Olympics," he admitted. "But it's not the only one, because the greatest dream would be the World Cup. It's one of my objectives.
"Certainly, the World Cup is far away, but I imagine myself playing in the jersey of the national team and becoming champions in our own country. I cannot stop thinking about it!"
Lucas, who can play as an attacking midfielder or out wide, is just 19 but has already been capped 11 times by Brazil.
Since March, Goal.com has been publishing exclusive extracts from Luca Caioli's new book Ronaldo: The Obsession for Perfection. Friday's excerpt looks at how Cristiano and Portugal lost out in the final of Euro 2004. Don't miss it!