When I was younger, a longgg time agooo, I did that with a guy not nearly as fast as Powell, but he was a lot faster than me. He could run around 10.6 for 100 meters, while I could't do much better than 11.6, but I was trained for the 800/mile. This other guy was a pure 100/200 guy (21.2).
The challenge was over in a remarkably few runs. On the first one, on which he stayed a half step ahead of me, was a joke for him. The second one, he had trouble staying ahead of me comfortably, as he kept trying to slow down and I was happily sprinting as fast as I could. On the third one, I actually beat him, as he misjudged the finish line and slowed just a touch too much. He rallied to beat me on the fourth one, but he was toast from that point on.