SAN FRANCISCO -- Just when it seemed as if Oracle Team USA might fritter out quickly, the defending champion won its first America's Cup race in dramatic fashion Sunday, breaking the winning streak of Emirates Team New Zealand and giving the team hope of keeping the trophy in San Francisco.

It wasn't easy. The American team was down three races -- losing Race 3 on Sunday afternoon after giving up an early lead -- before winning Race 4 by eight seconds.

"A lesser team would have crumbled in the fourth race," Oracle Team USA skipper Jimmy Spithill said after the races Sunday. "This team is very good under pressure and will run itself into the ground if that's what it takes. It feels good to shift the momentum over to us."

Emirates Team New Zealand (l) and Oracle Team USA compete during the 34th America’s Cup on September 8, 2013 in San Francisco.    AFP PHOTO/Don
Emirates Team New Zealand (l) and Oracle Team USA compete during the 34th America's Cup on September 8, 2013 in San Francisco. AFP PHOTO/Don EmmertDON EMMERT/AFP/Getty Images ( DON EMMERT )

Last week, before the 34th America's Cup began, Spithill had called his team the underdog, a comment few believed given the backing by Oracle CEO Larry Ellison, who assembled what he considered the best racing and design team in the world. The losses in its first two races Saturday and the third Sunday made it seem as if Oracle could be headed toward a shutout in the best-of-17 regatta.

Spithill blamed sloppy tacking maneuvers for part of its problem.

"We need to keep improving. That's the name of the game," Spithill said. "There's no question these boats are physically the most demanding we've ever sailed. It's 30 minutes nonstop. It's relentless."

Races 5 and 6 are scheduled for Tuesday, beginning at 1:15 p.m. Because Oracle Team USA was docked two races (or points) over a cheating scandal involving 45-foot catamarans used in the America's Cup World Series last year, the official score is 3-0. Oracle still remains in the hole by one race (or point). The first team to win nine points wins the America's Cup. For Oracle, that means winning 11 races.

After racing virtually untouched in the Louis Vuitton Cup challenger series all summer -- its only defeat was because of a mechanical breakdown -- Emirates Team New Zealand suffered its first actual racing loss Sunday. It also was the first time team manager Grant Dalton, who is 56 and the oldest sailor in the competition, didn't crew.

"I'm sure he'll make a point of mentioning that," New Zealand skipper Dean Barker deadpanned.

He hopes the loss will make the Kiwis stronger.

"We certainly knew coming into this event it was going to be very, very close," Barker said. "You don't like losing races, but a lot of good things can come out of it that will make us better on Tuesday."

Both races Sunday showed the intensity and drama that has long been promised by event organizers. Over the course of both races, spectators watched dramatic mark roundings, penalties, close crossings and a mistake that sent the Oracle boat into a nose-dive.

Oracle positioned itself best at both starts and was first to round Mark 1 in both races. But in Race 3, Oracle allowed New Zealand to overtake it on the upwind leg, a lead the American team couldn't take back.

In Race 4, Oracle Team USA started aggressively and rounded the first mark six seconds ahead of New Zealand. The Kiwis kept close downwind, rounding the leeward mark only five seconds behind.

Heading upwind, the same leg New Zealand overtook Oracle in the earlier race Sunday, Oracle maintained dominance and widened its lead. By the third mark, the American team was ahead by 16 seconds.

New Zealand powered up on the downwind leg, getting within five seconds at the fourth mark, before drag racing to the finish line. Oracle kept its lead, finishing eight seconds ahead of New Zealand and capturing its first America's Cup win.

34TH AMERICA'S CUP

Emirates Team New Zealand 3,
Oracle Team USA 1

Best-of-17 series
Tuesday: Races 5 and 6, 1:15 p.m. and 2:15 p.m. 1 p.m. on KNTV
Thursday: Races 7 and 8, 1:15 p.m. and 2:15 p.m. 1 p.m. on KNTV
Saturday: Races 9 and 10, 1:15 p.m. and 2:15 p.m. 12:30 p.m. on NBC Sports Network
Sept. 15: Races 11 and 12, 1:15 p.m. and 2:15 p.m. 12:30 p.m. on NBC Sports Network
Sept. 17: Races 13 and 14, 1:15 p.m. and 2:15 p.m. 1 p.m. on KNTV
Sept. 19: Races 15 and 16, 1:15 p.m. and 2:15 p.m. 1 p.m. on KNTV
Sept. 21: Race 17, 1:15 p.m. 12:30 p.m. on NBC Sports Network
Sept. 22, 23: Reserve days
NOTE: Because of penalties imposed on Oracle Team USA, it must win 11 races to retain the America's Cup.