There’s nothing the on the water umpire’s like better than a good old dust up on the race course. Yet even when situations look fairly straightforward to onlookers, the level and sophistication of the umpiring system is impressive to see.

I rode with International umpires Bill Edgerton, Maria Torrijo and Shane Borrell in the semi final match between Emirates Team New Zealand and Mascalzone Latino to see what was involved.

For each race, each umpire assumes the role of one of the boats for the duration of the race and talks both what is happening, what the options and intentions are, as well as calling out the relevant rule numbers as the play rolls out. Meanwhile the third man, in this case Bill Edgerton acts as an observer, feeding in additional information and adjudicating when necessary. At times it gets pretty noisy and complex.

In this clip the Kiwis and the Italians come together on the downwind leg as they approach the leeward gate.