The boats are not allowed to have engines, so Team New Zealand's pedaling powers the hydraulic systems used to maneuver the wingsail and the daggerboards, or retractable centerboards, that are tipped with hydrofoils.
Before the regatta in Bermuda, all of the competing syndicates, except Team New Zealand, agreed to a blueprint for the next two editions of the Cup.
Spithill was widely reckoned to have the advantage over young Kiwi helmsman Peter Burling, a seven-time world champion and Olympic gold medalist in the 49er class in Rio previous year who despite his credentials came in with far less match racing experience.
In Race 5, Spithill, an Australian, crossed the starting line a split second too soon and had to drop two lengths behind Team New Zealand.
Spithill took a change on gate four, which did not pay off and found speed before edging in front at the next gate and was not to be denied an elusive victory.
Oracle's boat clearly was faster than the opening weekend wipeout, when the Kiwis won four straight races by margins from 30 to 88 seconds.
Ainslie, the most successful Olympic sailor and team principal and skipper of Land Rover BAR, said it had been tense.
BERMUDA-Larry Ellison's third-consecutive America's Cup is within reach: All he needs to do is engineer one of the greatest comebacks in sports, version 2.0.
In the finale of the 2017 youth event, the New Zealand crew needed to finish three places above the British in the last race to retain the trophy.
"They've got this history of innovation", Coutts said.
That could all change if the USA holders are able to turn around a 3-0 Kiwi lead in the first-to-seven competition on Bermuda's Great Sound when racing resumes this weekend.
Land Rover BAR sailing team manager Jono Macbeth said: "Land Rover BAR believe in investing and mentoring the next generation and alongside our long term aim to win the America's Cup for Britain, we will continue to nurture home grown talent to ensure a lasting legacy and sustainable future for young sailors".
"We also managed to get out for three training sessions as well, to sharpen up all those little things, those little scenarios". They revealed this week that TNZ's boat was considerably lighter than Oracle, due to carbon-fibre technology developed in-house, as were the crew overall.
"Both Pete and Glenn are a massive asset to the design team because they are intimately involved in everything we do".
Schedule: The dates of the Match extend from June 17 to 25, though will end earlier when a team scores 7 points.