Rain rain go away, sleepover boys want to play

So of course, we have a boys sleepover, and it bloody rains. So, no nets up in the garden, and 3 10yr olds now so full of energy and bored of playing Buzz. 

I'm going to have to let them out. 

My lawn is going to be a mud bath, like last time, see below. Buggar.

Bear in mind this was green before. Lushly green. Like a lawn should be.

The particularly barren patch to the left is the goal. Clearly.