America’s Cup ’92 : Kiwis’ Backup Looks Better, Too : Sailing: After mechanical failure on new boat, Davis pilots backup boat to victory in practice race.

SAN DIEGO — Two races, two victories for New Zealand--in two different boats.

So what? The current series of practice fleet races among the America’s Cup challengers is meaningless, except for what it portends when the trials start Jan. 25.

And that is plenty.

The Kiwis introduced their radical fourth boat Saturday and walloped the fleet. They had planned to race it again Tuesday, but after a hydraulic ram controlling tension on the forestay broke after the boat had sailed out to the race course, skipper Rod Davis jumped onto Russell Coutts’ backup boat.

Davis was the only common denominator with Saturday’s victory, demonstrating the depth of the New Zealand operation.

Coutts was ill from the virus that’s running through the Kiwi camp. Davis also has been fighting the flu and a cold but, with tactician Peter Evans and navigator Brad Butterworth, was well enough to win again Tuesday.

Iain Murray’s Spirit of Australia, steered by Peter Gilmour, led at the first two marks, with New Zealand second. Some observers thought Spirit was over the starting line before the gun, but the Kiwis caught up and passed on the second windward leg to finish first by a couple of boat lengths, followed by France, Nippon Challenge, Spain, Italy and Syd Fischer’s Challenge Australia.

The race was run over two windward-leeward laps in a steady drizzle and winds building from 10 to 17 knots during the race.

Il Moro di Venezia, which didn’t participate Saturday, didn’t sail its newest boat, either. Skipper Paul Cayard sailed the No. 4 boat--the one that won the International America’s Cup Class world championships last May--because No. 5 was having work done on shore.

The Italians were last at the first mark and lost hope of a comeback when two spinnakers blew out. They nipped Challenge Australia for sixth place after passing on the final jibe.

New Zealand planned to use its new boat today when racing resumes in the week-long tuneup series. Italy’s plans were uncertain.

Dennis Conner’s Stars & Stripes again drew attention from the challengers’ chase boats. Conner was on a fund-raising tour in the East, and with John Bertrand at the helm, the boat retired after breaking a block on a running backstay, before it even had a chance to join the chase.

Bill Trenkle, Conner’s operations manager and headsail trimmer, was recovering from a Monday accident and watched the race from the tender Betsy.

Trenkle was struck in the mouth by a stripped gear when a winch tore loose from the deck under heavy load. Several teeth were chipped and he needed 20 stitches inside and outside his lower lip.

Navigator Lexi Gahagan said the gear flew past two other crewmen to hit Trenkle.

“It was one in a million,” Gahagan said. “If it had hit him in the head it might have killed him.