Slim Hayden Panettiere Plays Tennis in a Bikini!

USMagazine, Thursday, April 12, 2012, 2:20pm (PDT)

They're just months away from celebrating their one-year anniversary, and by the looks of it, Hayden Panettiere and New York Jets wide receiver Scotty McKnight are more in love than ever.

Wearing a bright pink bikini, the Scream 4 actress, 22, shared a passionate kiss with her athlete beau -- and grabbed his firm booty! -- while vacationing in Hawaii Sunday. The following day, the half-naked duo played tennis together.

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"She's so competitive," a source at the Ritz-Carlton tells Us Weekly. "She wanted to beat Scotty on every stroke. If she missed, she was upset with herself, but then would laugh. And Scotty would run over to the net and kiss her."

The couple also dined with McKnight's parents at Merriman's in Maui on Tuesday. "Lovin' Hawaii with my man," Panettiere tweeted.

Panettiere, a longtime animal rights activist, was in town to volunteer on behalf of the Pacific Whale Foundation. She began dating McKnight, 24, in June 2011 after meeting him through mutual pal Mark Sanchez, 25.

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"I'm a huge Jets fan and became very good friends with Mark and his buddies," the actress told Us last year. "I've always been that girl who has a lot of dude friends. I'm into sports so we have a lot in common."

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Prior to her relationship with McKnight, Panettiere was in longterm relationships with heavyweight boxer Wladimir Klitschko, 36, and Heroes actor Milo Ventimiglia, 34.

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