There was no mercy for Sports Illustrated's cover girl Kate Upton, who as a guest on Ellen DeGeneres' talk show Thursday was pressed by the host to confess she's dating New York Jets quarterback Mark Sanchez, 25.

But Upton, 19, never admitted to it — at least not in so many words. The model kept coy as DeGeneres jokingly quizzed her, trying to get her to spill the beans. "How does your boyfriend Mark Sanchez feel about all this? He must be proud, right?" DeGeneres asked, referring to Upton's high-profile cover shoot. Upton remained tight-lipped. "Even if I had a boyfriend, I wouldn’t ask how he felt about it," she replied, giggling.

After getting Upton to admit that she'd met Sanchez, DeGeneres leaped to a conclusion. "So now you're dating him? How long have you been dating?" DeGeneres asked. "I don't know what you're talking about!" Upton insisted.

The round of questioning and denial continued as DeGeneres brought out a picture of Sanchez, which Upton agreed was cute. "She's dating Mark Sanchez!" DeGeneres concluded.

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