Former America's Cup skipper Chris Dickson predicts Team New Zealand will extend the deadline for challengers for their Auckland defence.
Only three entries are confirmed for the 2021 regatta and late entries must be submitted with the Royal New Zealand Yacht Squadron (RNZYS) by 5pm Friday.
So far, Italian challenger of record Luna Rossa, Sir Ben Ainslie's INEOS Team UK and American Magic from the New York Yacht Club have declared their interest.
With only four boats confirmed, Dickson told The AM Show that he wasn’t excited about the 36th edition of the regatta.
"If you have a party, and there is just me and three others coming, then it's not really a party," he said. "I think they need more.
"They say there will be more. Late entries close today, but they're allowed to take late entries until the end of the year.
"They're out there hustling, trying to get more boats there. Oracle did it last time, they got the Japanese team, which they pretty much owned and financed, but Grant Dalton needs a few more players.
"We know there are six that are being talked about, two of them quite seriously, but all we know now is that we have Team NZ and three other teams."
According to SailWorld.com, the six consist of two from the United States, two from Italy, and one each from Norway and China.
Additional reports suggest two Dutch yacht clubs, based in Muiden and Rotterdam, have been communicating with the RNZYS.
Teams must meet strict guidelines, if they want to compete in Auckland, 2021.