SAN FRANCISCO (AP) -- Might a British knight be able to help turn around the America's Cup misfortunes of defending champion Oracle Team USA?
Sir Ben Ainslie, the most successful Olympic sailor ever, subbed for struggling tactician John Kostecki during Oracle's training session Wednesday on San Francisco Bay.
Syndicate CEO Russell Coutts said skipper Jimmy Spithill will make the decision whether Ainslie replaces Kostecki for Races 6 and 7 on Thursday against Emirates Team New Zealand.
''I think he's thinking that's what we'll do,'' Coutts said.
Ainslie has been serving as helmsman of Oracle's B boat, helping prepare Spithill for the competition.
''You've got to remember, changing personnel at a time like this has never worked in the past so we've got to be cautious about making a change like that,'' Coutts told The Associated Press. ''We wouldn't be thinking about it unless it had a really good chance at working.''
Ainslie and Spithill didn't immediately return calls seeking comment.
Oracle must submit its crew list by 9 a.m. PDT Thursday. Race 6 is set for 1:15 p.m. and Race 7 for 2:15 p.m.
While Spithill has been aggressive and dominating at the start of races, tactical blunders and the Kiwis' dominance while sailing upwind have put the defenders in a deep hole.
Kostecki called for a foiling tack in Race 5 on Tuesday that led to a crushing loss to Team New Zealand. The American powerhouse was so soundly beaten by the plucky Kiwis that it played its one postponement card for the regatta and called off Race 6 in order to regroup and make changes.
The Kiwis lead 4 to minus-1 and need five wins to claim the oldest trophy in international sports. Oracle Team USA, owned by software billionaire Larry Ellison of Oracle Corp., was docked two points by an international jury in the biggest cheating scandal in the 162-year history of the America's Cup. It needs to win 10 races to keep the Auld Mug.
Coutts, who won the first two of his four America's Cups as skipper of Team New Zealand in 1995 and 2000, said Ainslie might make a difference.
''He's obviously an extremely accomplished sailor, but Jimmy and Ben and Tommy Slingsby haven't worked together yet,'' Coutts said. ''That's a pretty big ask at this point in the regatta.''
Slingsby, who like Ainslie won a gold medal at the London Olympics, is the strategist and a grinder aboard Oracle's 72-foot catamaran.
In the 1992 challenger finals, New Zealand Challenged benched American-born skipper Rod Davis and tactician David Barnes, replacing them with Coutts and Brad Butterworth for the final two races. It didn't help, as the Kiwis lost both races to Italy's Il Moro di Venezia. In the 2003 America's Cup match, hard-luck Team New Zealand replaced tactician Hamish Pepper with Frenchman Bertrand Pace before Race 4. New Zealand went on to lose 5-0 to Alinghi of Switzerland, which was skippered by Coutts.
During Wednesday's training session, Ainslie was wearing a life jacket with Kostecki's name on the back. Coutts said that was only because Kostecki's gear had certain communications equipment in it. During a two-boat training session last week, Ainslie was steering the backup boat while wearing gear with Coutts' name on it.
Ainslie, 36, has rallied from tough spots before.
At the London Olympics, he trailed the entire regatta before using spot-on tactics to win his fourth straight gold medal and secure his spot in games history.
In the final race, he pinned leader Jonas Hoegh-Christensen in the back of the fleet and finished ahead of the Dane to win the gold. He also has a silver medal from 1996.
Going into those games, Ainslie had been called Britain's greatest sailor since Admiral Lord Nelson, who was killed while leading his fleet to victory over the French and Spanish fleets at the Battle of Trafalgar. A statue of Nelson rises high above London's Trafalgar Square.
Ainslie felt that comparison was hype.
''I didn't rescue the nation from the depths of Napoleon Bonaparte,'' Ainslie said after winning the gold medal on the English Channel. ''You do the best you can do in your style of racing.''
Ainslie was knighted by Princess Anne in March.
Ainslie had another remarkable performance at Athens in 2004. Disqualified from his second-place finish in the second race due to a protest by a French sailor, the British star fought back from 19th overall to win the gold.
Ostensibly, Ainslie is with Oracle in this campaign in hopes of launching a British challenge for the 35th America's Cup. Britain has never been able to win back the silver trophy it lost to the schooner America in a race around the Isle of Wight in 1851.
There had been speculation that Coutts would join the crew Thursday.
''You've got to be kidding me,'' Coutts, 51, said with a laugh. ''We're not going to bring the geriatrics out.''
Coutts says he's too old to sail the physically demanding boats. Age, however, hasn't kept Team New Zealand managing director Grant Dalton, 56, from serving as a grinder on the Kiwi boat, although he was given a breather in the second race on Sunday.
Oracle's tactician must also help grind, turning the winches that help power the hydraulic system and trim the sails.
Team New Zealand tactician Ray Davies, by comparison, doesn't have to grind. That allows him to better keep an eye on the conditions and the other boat.
Kostecki had been one of just two Americans on Oracle's 11-man crew.
As much as improving tactics, Coutts said Oracle has to improve sailing upwind. That's what it was working on Wednesday, although the conditions were light.
Team New Zealand stayed ashore Wednesday.
''The boat's going really well,'' Davies said after Tuesday's race. ''We can't hide that fact and that does make life easier. If we just keep calm and don't make any silly mistakes, it's a very strong position.''
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