PHILADELPHIA -- Pandemonium erupted just before 2 p.m. across the metal bleachers at historic Franklin Field on Saturday, making the stately old place vibrate and rattle. Throngs of yellow-and-green clad fans leaped to their feet, wildly shook Jamaican flags, pounded their noise makers and belted out cheers.

It was, in short, a pretty animated hello.

The applause had nothing to do with the high school race just about to get underway on the track; it was generated solely by the mere entry onto the stadium infield of the world's fastest man, Jamaican Usain Bolt, who sauntered out for some easy sprints about an hour