Missed action

Antti needed a couple of action shots from the pump track for the local Mtnbike assosiation newsletter (or something, not sure about it...)

I'm always finding capturing action VERY challenging.
Challenge number one is the very basic: to get the camera focus where I want it to focus. Pretty often I miss it and the focus is in the background. (I'm using the AI SERVO mode trying to follow the moving person. When I get thrustrated with myself, I just switch to the auto mode which I hardly ever do other than in action situations).
Any hints?

Did also some treatment, for fun. Not much.

Good night!