Crewmen from the America's Cup team Young America worked today to ready their backup boat for racing after severely damaging and nearly sinking their race boat in strong winds and choppy seas off Auckland, New Zealand, yesterday.

"We're still in the game," said spokeswoman Jane Eagleson. "We're lucky. We have a two-boat program and we're hoping to get our other boat ready to race by Friday."

The first of the New York Yacht Club's $4 million, charcoal-black entries cracked in the middle like a brittle fortune cookie after hitting a pair of six-foot waves in 20-knot winds in the Hauraki Gulf. It seemed so certain to sink, skipper Ed Baird ordered all hands off. They leaped but the crippled boat miraculously stayed afloat and after being fitted with pumps and inflated air bags was towed slowly back to port.

Baird, a former world match racing champion from Florida, said hitting the waves was "like hitting a pothole on the freeway when all the tires blow out. It happened all at once." In this case the deck and hull cracked and the boat bent into a banana shape. Baird said he'd "been on plenty of broken boats over the years but I never had to jump before."

A repair crew flew in overnight from Goetz Custom Boat Works in Rhode Island, where the 75-foot carbon-fiber hull was built, to patch crippled USA 53, which is not expected to be seaworthy for weeks. Meantime, Young America's newer Cup boat, USA 58, will be beefed up and substituted for racing as soon as possible.

Under regatta rules, teams with two boats can ask for permission to switch in the middle of a round-robin if the first boat is damaged beyond immediate repair, though they must forfeit the next scheduled race. Young America was to race the Swiss boat FAST 2000 today, but storm winds blew in, postponing that race till Thursday.

Eleven Cup challengers are in their second round-robin, one month into a four-month series of races to determine who gets to sail against Team New Zealand for the Cup in February. Before the crack-up, Young America was second in the standings with a 10-2 record and considered a strong contender.

The catastrophic failure was eerily reminiscent of the first and only sinking of a Cup boat four years ago, when OneAustralia broke in two and plunged to the bottom in similar conditions off San Diego.

OneAustralia skipper John Bertrand watched from a spectator boat yesterday and said: "It's a remarkably similar situation to our boat sinking. The bend in the boat is very similar, but our keel ripped the hull apart underneath. This appears to be a compression failure through the deck. It didn't rip apart the hull, otherwise it would have sunk."

Young America was towed in with bow and stern ends pointed high in the air and the deck almost awash.

Said skipper Baird: "The boat folded and the boom crashed on deck. I don't remember the sound. My first thought was to make sure the guys were okay. Then the boat folded some more and it sounded like it wasn't going to stop. It was time to jump in but the hardest part was swimming in all that wet-weather gear."

Support boats and tenders from other boats helped rescue the struggling crewmen. Young America was 26 seconds ahead of the Japanese entry Nippon with three miles to go in an 18-mile race. Nippon's tender, as well as support boats from undefeated Prada, elsewhere on the course recording its 13th straight win, assisted.

Overnight, Young America's brain trust huddled by phone with engineers from the office of designer Bruce Farr in Annapolis, trying to determine what made the deck snap.

"It's substantial damage in one sense," Baird said. "We were very lucky to get it ashore. In another sense it's not as bad as it could have been. The internal structures are all intact, as are the rudder and keel and mast and bow and stern sections. It's just the hull and deck in the middle that failed, and we have to fix it."

Asked about the likelihood of the same thing happening to USA 58, leaving Young America with no boat to race, syndicate chief John Marshall said: "The structural layout of the boats is very similar, so we are concerned. The prudent thing is to put extra reinforcing in, which we're doing. We want to compete in the rest of the round.

Added Baird, "We don't know what it is that failed on 53 yet, so we really don't know what to look for."

Notes: Racing in the Cup was canceled today (Wednesday) because of bad weather. Winds on the two courses on Auckland's Hauraki Gulf were gusting at 35 knots, twice the 18-knot ceiling for racing.