Anyone know what this game is? And, in particular it's name so I can search properly for it?
EDIT: Excellent! Thank you, everyone. It's Cricket (played with a straight, slightly flattened 'cricket bat'), which should be played on a rolled, flattened field or alternativey, field hockey (played in fields with a curved stick similar but not identical to ice hockey sticks) a more casual game and 'muddy' is a frequent vistor to field hockey.
While I was originally thinking of cricket, I think that field hockey will actually work better for my story - so everyone was right! Yay!