"I turned up at 6am in my gumboots, which didn't come off all day. They were quite snazzy - a croc skin variety, not real obviously - with a decent heel on them.
"The actual day worked fine, it was beautiful weather. Everyone came in lovely outfits and took it in good spirits. It was a case of either enjoy yourself, or sulk. Fortunately everyone chose the former."
Marshall has seen the best and the worst of conditions. The 32-year-old local has been involved at the event for the best part of a decade after emigrating from England. She took up the sport while attending the Royal Agricultural College (now University) in Cirencester.
"This year we've put in loads of new infrastructure to handle the rain better. Other than a massive natural flood, we should be alright.
"There's a new road around the field, so you don't have to leave the grass. Last year's that's what became problematic because it turned to slush.
"Obviously the event won't run without the sport, so our preparations have been to get the field as good as can be. We've put nearly 600 tonnes of sand on, and it's been worked on nearly every day for two months."
Nonetheless, socialising is a key element to the day.
Observing fashion etiquette ranks close in priority to wielding a polo mallet. Summer dresses and teetering heels are the order of the day for women. You can almost hear Achilles tendons squealing for mercy, especially during the halftime tradition of "treading the turf".
Marshall recommends a graceful pirouette.
"It's not only a way to show off your outfit; it's actually important to smooth out the field.
"If it's wet like last year the spectators have a serious function, and it is really appreciated.
"Just give [the dirt] a little tap with the front of your foot and spin on your toes."
Men tend to don the sport's eponymous shirt or slip into a bespoke suit. Straw hats are set at a rakish angle; sunglasses are often mirrored.
In a nod to rugby sevens, when the glasses stop clinking and the hands stop shaking you can always watch the action as a commentary booms through the PA.
The athleticism and agility of the riders and ponies – as horses are known in polo-speak – is riveting, especially alongside requisite hand-eye co-ordination.
Those in the saddle possess yogi-like core strength to swivel, swerve and swat the 8cm diameter ball at speeds of up to 50km/h. They give it a decent clonk, too. A mate took one in his bespoke-suited shoulder a couple of years ago. He wore it stoically, but gave it a rub when attention was diverted.
Brit James Harper married a Kiwi groom from Hamilton, and has come to the open for the last four years. The event forms part of an international circuit which has taken him to an alphabet of countries; namely the fields of Argentina, Australia, Brazil, Chile, Dubai, England, Italy, South Africa, "pretty much all of Europe", "a little bit of America" and the snow of China and Switzerland. The Cowdray Park club in west Sussex is home.
"I always rode as a kid and, after playing lot of rugby at school, I was getting to an age where you pick girls and footy over riding. Then they showed me this sport. I got the bug on the first day."
Harper will play for the Knight Frank team alongside the Wood brothers, Charlie, Jimmy and Henry.
"They are coming up from the South Island [north Canterbury] and have put in a bloody good effort to bring 32 horses.
"They're going to give me seven or eight for the six chukkas. What you do then is pick the best three or four. They might come out twice [in a match] and the others come out once.
Harper says the ponies and the grooms also play pivotal roles.
"The horses are expected to do everything; go as fast as they can off the mark and stop just as quickly. It's pretty amazing what we ask of them.
"You're and riding and practicing every day, especially going from country to country. Two to three days on them and you've got a good idea how they'll go. Confidence in your horses is vital.
"You've also got to have trust in the grooms who spend most of the time on them. Everyone is hands-on in this sort of set up, but good grooms make a big difference."
Marshall says fortunately the event is well-regarded enough that they don't have to "petition too heavily" for quality players, especially with spaces in only six teams on offer.
Regardless of the victor, one part of the day remains her favourite.
"Seeing the champagne sprayed at the presentation. For me, that signals the end to a year's work with everyone finishing safely and happily.
"There's camaraderie and a look of elation not only from the players but the grooms, patrons, families and girlfriends as they join in. Everyone's cheering and you can feel the delight in what they've achieved."
Polo facts
- The final consists of six seven-and-a-half minute chukkas.
- Teams consist of four players who will often ride more than one pony per chukka
- Polo ponies can take anywhere from three to five years to train after generally being taken from the racing track as three-year-olds.
- Mallets must be used right-handed.
