How does he draw the rest of the lady? Assuming this was before AI.

I have no idea, but it's impressive. And yeah, this guy has been doing this for years before AI.

The angle and colour of 2458 changes to being almost perfectly horizontal so err...wow...did AI fill that all in?!

Evidently AI needed to be given new information for the 2458 and that might be what gives it away.

I love seeing this dude's stuff, always a light hearted monkey's paw deal

Going with the 'not AI' assumption, if there were more pictures he might have been able to use one where she was more visible.

If you look at her face it isn’t quite as well done as the body. And the racing number is a completely different style than all the other runners in the race. So my hypothesis is he found some other photo of runners taken from a similar angle, copied a body from that photo to this photo (except the right arm), and then hand edited the face/edges to make it match.