SAN FRANCISCO -- What a difference seven weeks made for Ben Ainslie.

The four-time Olympic gold medalist struggled in August during his debut as a skipper in America's Cup World Series competition. Thursday, he showed he used the intervening time wisely, finishing first and third in the opening fleet races of this second round of elite sailing on San Francisco Bay.

"Just practice, just time on the boats," said Ainslie, who now leads the pack despite never competing on catamarans before August. "From a long way out they might look quite graceful and fast, but they're incredibly hard to sail. There's lot of techniques to get right."

Ainslie, who ended up 10th among the 11 boats in August, is representing Great Britain as helmsman of the JP Morgan BAR team. But he also is working with Oracle Team USA as it prepares its defense of the America's Cup next summer.

The Oracle captain that Ainslie is expected to push, Jimmy Spithill, easily won the second race Thursday after an out-of-character eighth-place finish in the first. The win was enough to catapult Spithill into a three-way tie for second place with the other Oracle boat skippered by Russell Coutts and Sweden's Artemis Racing Red.

Ainslie noted that Spithill and Coutts shared their knowledge of the 45-foot catamarans with him.

"That's a huge asset to be able to tap into that for a newcomer to multi-hulls and this type of racing," Ainslie said.

Spithill led the second race from the start and finished 37 seconds ahead of Artemis Racing Red with new skipper Nathan Outteridge.

"We just got our act together, really," he said. "The first one, we just made a lot of mistakes, which was pretty disappointing. Obviously the pressure was on for the second one and it was nice to bounce back and get the result."

  • Match tournament quarterfinals were spread over two days, and in Thursday's races, Emirates New Zealand eliminated the Energy Team and Artemis Racing White ended Team Korea's chances.

    Oracle Team USA's two boats will race Friday with Spithill facing Ainslie and Coutts going against Artemis Racing Red.

    Coutts, the defending match champion, liked that draw.

    "The good thing for us is that Ben and Jimmy race each other tomorrow and one of them comes in second," Coutts said.

  • Sharing the shoreline with Fleet Week has meant that much of the racing is later in the day than it was in August.

    And that has meant far different -- and in some ways, more difficult -- sailing conditions, as China Team found out in its initial day of racing when the wind-control structure for its wing was damaged bouncing around the bay's rough waters.

    "It was really steep chop," said China Team skipper Phil Robertson. "It was classic wind against tide because we're skating so much later. It was very, very rough."

  • While this week's competition involves 45-foot catamarans, Murray gave a preview Thursday of what to expect next year when the more powerful 72-foot versions will be competing for the America's Cup.

    Both Oracle Team USA and Emirates New Zealand tested the bigger boats earlier this week.

    "What we have is something that's trying to act like a plane," he told a luncheon audience at the Golden Gate Yacht Club, adding that Oracle's boat needed extensive repairs after foiling at high speed.

  • Here are the standings after the first two fleet races: JP Morgan BAR 21, Oracle Team USA Spithill 16, Oracle Team USA Coutts 16, Artemis Racing Red 16, Emirates Team New Zealand 14, Artemis Racing White 12, Energy 11, Team Korea 10, Luna Rosa Piranha 9, China Team 7, Luna Rosa Swordfish 2.