Justin's Replacement?

Cameron Diaz got a whole lot of personal attention from surf champion Kelly Slater during a private surf lesson in Hawaii this week. In fact, the surf god could barely take his eyes off Diaz as the pair shredded waves on the North Shore of Oahu.

As TMZ first reported, the two have been spending a lot of time together in the wake of Cameron's split from Justin Timberlake. We're told the duo hit various golf courses and restaurants on the island ... and that Diaz is shacking up at Slater's island home.

Cameron was often seen hangin' ten with former flame Justin Timberlake. A distant memory. Cowabunga dude.