Who knew? Lil Wayne is a tennis fan!

In a hand-written letter to Sports Illustrated, the platinum-selling artist (real name: Dwayne Michael Carter Jr.) made some predictions from prison regarding the upcoming U.S. Open. He got into tennis, he writes after trying to play and finding it "unbelievably difficult."

"I'm a huge [Rafael] Nadal fan," he says. "I'm definitely rooting for him to get the Grand Slam and win the U.S. Open." He cites Nadal's primary opponents as Roger Federer, Andy Roddick, Andy Murray and Novak Djokovic.

"Nadal wins it all," he repeats. As for the women, Lil Wayne says he's rooting for Kim Clijisters to take the title.

Sadly, the rapper won't be able to attend any of the matches. He's currently serving a year-long sentence for gun possession.