SAN FRANCISCO — The head of America's Cup challenger Emirates Team New Zealand has accused defending champion Oracle Team USA of cheating in the latest controversy in sailing's premier regatta. Oracle Racing last week admitted it modified its boats without permission of the Measurement Committee during four regattas in the America's Cup World Series, a warm-up to this year's regatta. Those regattas were sailed in 45-foot catamarans, which were prototypes of the 72-foot catamarans being sailed this summer in the America's Cup. “You can't actually get to any other point than the fact they were cheating,” Emirates Team New Zealand managing director Grant Dalton told the San Francisco Chronicle Tuesday. “It's really serious.” The international jury is investigating and could punish Oracle with a fine, forfeiture of races or disqualification from the America's Cup. Any punishment would be another smudge on already troubled regatta. The best-of-17 America's Cup match begins Sept. 7 between Oracle and the winner of the Louis Vuitton Cup for challengers. Emirates Team New Zealand faces Italy's Luna Rossa in the best-of-13 Louis Vuitton Cup final starting Saturday. — AP