At his media session Friday, however, Dorsett declined to take the bait in making a prediction for his 40 time.
"I don't have one," Dorsett said. "I'm just going to go out there and run as fast as I can because I've been training hard for this. I know a lot of people will be watching when I'm running and I don't really worry about that, I just do what I'm going to do."
Dorsett didn't tip his hand, but he did confirm why he is in the running to chase down Johnson's top time.
"I ran a lot of 40's at Miami, but it's all hand-timed. I ran a lot of 4.2's, but it's hand-timed, so it doesn't matter. Only thing that matters is what that clock says."