Only four foreign challengers met the deadline to enter the Louis Vuitton Cup next summer to determine the opponent for Oracle Racing in the 34th America's Cup.
They are Sweden's Artemis Racing, Emirates Team New Zealand, Italy's Luna Rossa Challenge and Team Korea.
The Louis Vuitton Cup will run from July 4 through September 1, 2013, on San Francisco Bay, followed by the America's Cup match from September 7-22.
Oracle Racing says it will hold defender trials to strengthen its bid to defend the Cup.
Jimmy Spithill, who skippered the team to victory in the 33rd America's Cup, will helm one of the boats, while Ben Ainslie, the British star who is currently trying to win his fourth straight Olympic gold medal, will helm the other. They will go head to head on the same racetrack and on the same days as the Louis Vuitton Cup challengers.
Organisers knew the numbers would shake out from the original list of 14 challengers from around the globe. The sluggish world economy and a switch from sloops to catamarans caused several syndicates to drop out.
Teams must now finish building the 72-foot catamarans that will be used next summer. Currently, the America's Cup World Series is being contested in 45-foot catamarans.
There is some question whether Team Korea will have the funding to build a 72-footer.
Team Korea's skipper, Australia's Nathan Outteridge, is leading the 49er class in the London Olympics.
In a change to the old format in which a team needed to win five races to win the America's Cup match, there will be two races per day, with nine victories required to win the oldest trophy in international sports.