Kaley Cuoco Denies Having a 'Secret Fling' With 'Big Bang Theory' Co-Star

— -- Kaley Cuoco is setting the record straight.

The actress took to Instagram to respond to tabloid magazine rumors of a secret relationship she allegedly had with Johnny Galecki, her co-star on "The Big Bang Theory."

Cuoco admitted in a 2010 interview with CBS Watch! Magazine that she and Galecki had previously dated for almost two years, but the TV stars insist their relationship now is platonic.

"So sorry to disappoint, but no home wreckers or secret flings going on here," wrote Cuoco on Instagram. "Me and @sanctionedjohnnygalecki are just the best of buds - Leonard and Penny will just have to suffice!!!"

Galecki posted a similar photo on his Instagram page, backing up Cuoco's statements about their relationship.

"No scandals / home wreckers / pregnancies here, y'all. Just profound friendship," Galecki captioned the photo.

Cuoco announced her divorce from professional tennis player Ryan Sweeting in September after 21 months of marriage.

ABC News has reached out to Cuoco's and Galecki's reps for comment.