All but defeated a week ago, Oracle Team USA tied the faltering Kiwis 8-8 on the scoreboard by winning its 10th race overall. Oracle was docked two points for illegally modifying boats in warmup regattas.
If it hadn't been hit with the harshest penalties in the 162-year history of the America's Cup, Oracle Team USA's sailors would be hoisting the silver trophy in victory.
Instead, the epic 19th race is scheduled for Wednesday, weather-permitting, on San Francisco Bay.
Either Oracle will finish one of the greatest comebacks in sports history or Team New Zealand, marooned on match point for the past week, will get the elusive win it needs to claim the Auld Mug for the second time in 18 years.
Oracle, which trailed 8-1 last Wednesday, came from behind and passed the Kiwis after they tacked too early and slowed while zigzagging toward the Golden Gate Bridge. The American-backed boat - with only one American on its 11-man crew - sped past and built its lead to more than 1,000 yards on the windward fourth leg going past Alcatraz Island.
The final margin was 54 seconds. Spithill, a 34-year-old Australian who has been almost defiant about his team's ability to rebound from the penalties, did a flyby of Pier 27-29, with his crew lining the port hull to wave and pump their fists toward the crowd.
Earlier, Oracle forced Emirates Team New Zealand into two penalties during the wild start of Race 17 and won by 27 seconds.
The races were so pivotal that software billionaire Larry Ellison, who owns Oracle Team USA, skipped making a keynote speech before 60,000 people at Oracle Open World so he could witness the comeback firsthand from a chase boat on the bay.
Team New Zealand skipper Dean Barker dominated Spithill at the start and beat him to the first mark with his 72-foot catamaran, allowing him to control the race.
The Kiwis led by 7 seconds rounding the second gate mark before committing the blunder that cost them the lead and, perhaps, the oldest trophy in international sports.
In Race 17, Spithill appeared in trouble just before the start but hooked behind Barker into a favored leeward position as the boats jockeyed just inside the Golden Gate Bridge. The 72-foot catamarans touched, and Oracle tactician Ben Ainslie yelled at the Kiwis to tack away. They collided again, this time harder, with Ainslie gesturing angrily.
Team New Zealand sat dead in the water to clear the penalties as Oracle pulled away. Oracle stayed ahead the whole way around the five-leg course.
Spithill and his mates are the first to win seven straight races in an America's Cup match. There have been three five-race winning streaks when the Cup was best-of-9. This regatta started as best-of-17, but Oracle will need to win 11 races to keep the Cup.
Oracle has twice trailed by seven points, most recently when Team New Zealand won Race 11 on Wednesday for an 8-1 lead.
After Oracle won Race 12, Team New Zealand was denied the chance to seize the Cup when Race 13 was abandoned because of a 40-minute time limit with the Kiwis well ahead in light wind. When the race was resailed in better breeze, Oracle won to begin its winning streak.
With the two victories Tuesday, Oracle Team USA has won for the ninth time in 13 races since Ainslie, a British Olympic star, replaced American John Kostecki as tactician.