Footballing lesson

Football is a noun, but why is it used with an -ing form? I usually say "football lesson".

Manchester City teach Manchester United a footballing lesson in a 3-0 derby romping at Old Trafford.

You've somehow forgotten to cite the source of that sentence. We'll answer when you've done that.

I have provided the source. Could you explain?

It’s a common enough term used by sports writers/commentators.