I don't know the rules, exactly, but polo on Sachuest Beach (four chukkers' worth) was a scene. A sizable crowd (for February) gathered to watch the action ... or not watch the action, a large percentage of the onlookers being toddlers and dogs, and they were busy toddling and doing whatever dogs do.
Two refs in denim-and-black stood outside the fray on horseback (ponyback?) following the blue and yellow teams, three players each, as they galloped back and forth, sticks (or whatever you call them) in the air, toward Surfers' End then toward Sachuest Point, all the while chasing a little orange ball that hopped hopelessly over the increasingly beat-up beach.
Some horses/ponies were timid about the water — "hey, that's cold" — and tip-toed outside the froth, resisting the chase when it required getting outside their comfort zone. But all ponies were playing the game, knew just what they were doing — that much was clear — as their riders made shot after shot that went wide of the goal.
Footing became tricky (for everyone) as time wore on, so at half-time — or the polo equivalent — the crowd went out, just as they do during summer matches on grass, to smooth things over, fill-in the holes, make things right for the athletes (on two and four legs), i.e., polo fans participate, like a giant collective Zamboni.
It was over all too fast. Two quick chukkers later, Newport (in blue) finished on top, and everyone turned from those elusive-if-clearly-marked goals toward home ...