Credit: George Pimentel/WireImage; Frazer Harrison/Getty

Justin who?

Just five days after announcing her split with beau of four years Justin Timberlake, Jessica Biel was spotted cozying up to her Playing the Field costar Gerard Butler.

Currently filming the flick in Shreveport, Louisiana, Biel, 29, and the 300 hunk, 41, were first spotted out for a crew member's birthday at a Japanese restaurant on March 15.

"When Gerry got there, he made a beeline for Jessica," an eyewitness tells Us. "He was really flirting with her."

Two nights later, the duo was seen throwing back margaritas at a Mexican restaurant. And that's not all, Biel and Butler shared two more dinners later that week!

Still a source close to the actress says, "She only wants to be friends."

For all the details on their canoodling, check out this weeks Us Weekly.