Soft wind, low scores and an ace by Jordan Spieth

NASSAU, Bahamas (AP) Jimmy Walker had reason to believe he was simply playing golf on vacation.

He was at Albany Golf Club, located at the far end of New Providence island with a tropical feel even without views of the ocean. The air was warm. The breeze was gentle. And there was hardly anyone watching him play golf.

But there were leaderboards around the golf course at the Hero World Challenge. And there were familiar names - plenty of them.

British Open champion Zach Johnson and Paul Casey joined Walker atop the leaderboard at 6-under 66. Right behind were defending champion Jordan Spieth, Adam Scott, Brooks Koepka, Bill Haas and two-time Masters champion Bubba Watson.

''It feels pretty small,'' Walker said. ''But on a grand scale, it's a big event with really good players.''

And all of them played really well. All but one player in the 18-man of top 50 players in the world ranking broke par. The exception was Hideki Matsuyama, who was 1 under playing the 18th hole until he made a quadruple-bogey 8 and posted a 75.

Here's how Friday was shaping up:

JORDAN'S ACE: Two majors. Five wins. All the major awards. And then Spieth shows up for his final tournament of the year and makes an ace on the second hole.

It was a 6-iron from about 175 yards, and he didn't even know it went in.

''Absolutely flushed it right at the hole and didn't think it went in,'' Spieth said. ''I started walking because balls have been sticking on the green, so I thought it stuck. But I guess it just crept forward that extra 2 feet.''

Good thing he didn't have to buy drinks.

''That's probably going to get pretty expensive out here,'' he said.

Spieth opened with a 67 in his title defense, and he is pushing toward the finish line on Sunday.

''I'm ready for some rest,'' he said. ''This is a fun event for us because it's so relaxed, we're able to sit back and I'm not grinding as hard as I would on a normal week. Just trying to really soak it in as a half-vacation, half-tournament.''

NEW SWING: Walker has played a dozen times since his runner-up finish at the AT&T Byron Nelson, and his best finish was a tie for 18th in the 30-man field at the Tour Championship. In his last event, he missed the cut by two shots at the Dunlop Phoenix in Japan.

Maybe that's what persuaded him to follow the suggestion of Butch Harmon and introduce a new move in his swing. Walker turns his head toward the flight of the ball, much like David Duval. With minimal expectations, he ran off eight birdies in his round of 66.

The pro-am wasn't a great indicator because he spent so much time standing around. In twosomes Thursday he found his groove.

''We had a nice rhythm and I was able to kind of keep the good feeling going,'' he said.

GLAD TO BE HERE: Watson has been in the top 10 all year and usually plays in the Hero World Challenge. He didn't enter this year, however, because it moved from Florida to the Bahamas, and Watson didn't have the documents necessarily to bring his newly adopted daughter, Dakota, with him.

He already was away from home two weeks in a row for the Asia swing. He's playing Thailand next week, and didn't want another two weeks without his entire family. Watson told the tournament to call him if someone pulled out and he would check on those documents.

Jason Day pulled out to stay at home with his newborn daughter. Watson's wife went to Arizona to sort out the documents, and here he is.

''We're here legally,'' he said.

He soared into the lead with a 30-foot eagle putt, made double bogey on the 12th and then bounced back with three straight birdies and wound up with a 67.

HAPPY TO BE PLAYING: This is Dustin Johnson's kind of tournament.

''Golf in a cart, the beach. I could play in a tournament like this every week,'' he said on Tuesday.

And then he went diving that afternoon, and pulling himself back into the boat he sliced open his right heel. Johnson said he thought he only scratched it until he sat down and ''saw blood everywhere.'' He played the first round in tennis shoes and shot 67.

His kind of tournament.