The ‘mystery blonde’ who was recently seen enjoying the company of Jessica Simpson’s maybe-ex-boyfriend Tony Romo has been identified as one Lindsey Betrus.

It's claimed that, as reports were surfacing that his relationship with Jessica was over, the Dallas Cowboys quarterback was chatting up Betrus at a Chicago club.

And a source insists it was Romo who did all the running, telling Star, "Lindsey is a terrific, down-to-earth woman — and she's never been a Hooters Girl, as some people have mistakenly reported!.

"And as for her time with Tony, he was totally the aggressor that evening!"

Jessica's camp has so far dismissed the break-up rumours.

On Wednesday, her rep told E! Online, "Not true, not true! I spoke to Jess yesterday and the day before. They are still together."

The site also reported that Romo will be accompanying Jessica to her sister Ashlee's wedding to Fall Out Boy Pete Wentz this weekend.