Rocker John Mayer has urged American football fans to give his ex-girlfriend Jessica Simpson a chance, instead of blaming her for the poor performance of her sports star boyfriend Tony Romo.

Simpson has been berated by Dallas Cowboys fans for putting their star quarterback off his game in recent weeks.

But Mayer - who dated the Texan singer/actress for several months before their split in May 2007 - has pleaded with the team’s devotees to give her a chance.

Writing on his online blog, he says: "Dear Dallas and Surrounding Areas, this isn’t a sports blog, and it isn’t a publicity stunt. This is about doing what I think is right as a person, in this case speaking my mind.

"I have never known anyone to have more pride in their home state and their upbringing in it than Jessica Simpson has in Texas. That girl loves Texas more than you know. It’s one of her most defining traits as a person. So please don’t try and take that away from her."

And Mayer admits he doesn’t care if he is criticized for his defense of Simpson: "I can spare a Wednesday’s worth of bad press if it means sticking up for a good soul."