Was it too many Coca-Cola commercials and not enough training? Or perhaps the pressure of supporting an entire nation's Olympic hopes and dreams really was too much for one person to handle. Or maybe it was that new haircut that really didn’t suit.

Theories abounded this afternoon, but one question remained: What happened to Liu Xiang? China’s great track hero failed to qualify for the 110m hurdles final, pulling out before even completing his first race with what appeared to be a pulled leg muscle.

After a trio of lesser Chinese hurdlers successfully made it through the next qualifying round, expectations were running high for the defending Olympic champion. And when the golden boy finally appeared from the belly of the Bird’s Nest, the crowd went crazy. Chants of “Liu Xiang, Jia you!” reverberated off the Nest’s twisted steel walls. But the cries of joy were quickly replaced with sighs of agony and incomprehension as, after a false start by a Dutch runner, Liu quietly limped off the track.

There were signs of trouble early on. During the warm up runs, Liu pulled up suddenly after clearing two hurdles, kneeling briefly on the track and grabbing at his ankle. He walked gingerly back to the starting line and appeared ready to tough it through the first qualifying heat. But after the false start, it was clear he could not go on and walked away.

After that it was all a blur. I’m not really sure who won that race or who had the fastest qualifying time (someone named David or Darren?) since I, like the other 90,000 fans who had come just to see Liu, were too busy trying to figure out what just happened. Almost immediately, the stadium was emptied. Just like the hearts of the fans.

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