Fast on the track

Jaylen Bacon breaks from the blocks during a recent practice at the Arkansas State University Track and Field Complex in Jonesboro. He will be competing in the 100 and 200 meters at the NCAA Outdoor Track and Field Championships in Eugene, Ore.This track story begins the same way most track stories of the past decade begin: A snapshot of Usain Bolt.

The Jamaican sensation, holder of three world records, was running his final race.

It was the final leg of the 400 relay at the IAAF World Championships in London, August 2017, and Bolt had just received the baton.

What happened next has been told and retold: Bolt jolted, gimped and fell with a left hamstring injury; he denied a wheelchair, limped…