The 27-year-old newly single actor, who split with girlfriend Kristen Stewart, is said to be attending a wine-tasting weekend hosted by Reese Witherspoon with Diaz, reported a website.
"Cameron thinks Rob is really hot and is up for making a play for him. The fact that he's 27 doesn't bother her. She has known him for a while but decided to keep a respectful distance while he was in that relationship with Kristen Stewart. "But now he's single so as soon as she knew Reese was hosting a four-day wine-tasting weekend at her home in Ojai, she was quick to get in on the act," a source said.
The duo became friends after starring in 'Water For Elephants'. Diaz, 40, was last seen in a romantic relationship with New York Yankees baseball star Alex Rodriguez for a year.