'Supergirl' Serena chases down phone thief

New York - Serena Williams chased down a would-be telephone thief at a Chinese restaurant that had the 34-year-old American tennis star comparing herself to Supergirl.

The 21-time Grand Slam singles champion detailed her adventure Wednesday in a Facebook posting complete with her wearing a Supergirl outfit and sending a message for people to channel their inner superhero.

And another message was clear -- mess with Serena Williams at your own peril.

"Soooooo yesterday (Tuesday) at dinner the CRAZIEST THING happened to me. I was sitting enjoying some Chinese food and this guy stands next to me," world number one Williams said.

"And something (I have now dubbed it my SUPERHERO sense) told me to watch him. My phone was sitting in the chair but I just didn't feel right.

"Low and behold, this common petty thief grabbed my phone and swiftly left. I looked at the chair, than shouted 'Omg that dude took my phone!!'"

"Not thinking I reacted, I jumped up, weaved my way in and out of the restaurant and chased him down. He began to run but I was too fast. I was upon him in a flash!

"In the most menacing yet calm no nonsense voice I could muster I kindly asked him if he 'accidentally' took the wrong phone. While he was thinking of the right thing to say and eventually he said 'Gosh you know what I did! It was so confusing in there. I must have grabbed the wrong phone'."

The matter left Williams pondering her own super powers.

"Superhero? Maybe? Or HELL YEA!!" Williams said. "I've got the speed the jumps, the power, the body, the seduction, the sex appeal, the strength, the leadership and yet the calm to weather the storm. Always listen to your superhero inner voice. Fight for what's right. Stand for what you believe in! Be a superhero!

"When I got back into the restaurant I received a standing ovation. I was proud. I just showed every man in there I can stand up to bully's  and other men. It was a win for the ladies! Just because you are a lady don't be afraid to step up to any challenge and not be a victim but a hero!"

Williams has not played since losing a US Open semi-final to Italy's Roberta Vinci, costing her a chance at a calendar year Grand Slam.