Jessica Simpson Jinxes Tony Romo (Photos and Video)

was at Texas Stadium on Sunday to cheer on her new boyfriend, Dallas Cowboys quarterbackas the heavily favored Cowboys played the Philadelphia Eagles.

Wearing a Dallas Cowboys jersey with a pink number 9 (Romo's number), Jessica watched from a luxury box with dad Joe Simpson, as Romo played the worst game of his career, losing to the Eagles 10-6.

The 27-year-old Pro Bowler threw three interceptions and fumbled the ball twice, earning him a quarterback rating of just 22.2. Romo's average rating this year is over 100, with his previous low being when former girlfriend Carrie Underwood attended the game against the Eagles last December, which the Cowboys lost 23-7.

Some advice for Tony Romo? Leave the girlfriends at home!

View more photos and video of Jessica Simpson cheering on Tony Romo at the game below.