For the most part, the golfers worked alone, though some had swing gurus watching, and others consulted with their caddies.

Butch, as in Harmon, the swing guru.

And, he is not a follower of any swing guru as many on the tour are.

Rick Smith, Mickelson's swing guru, wasn't surprised.

On the range before yesterday's round, Woods hit balls as Butch Harmon, his swing guru, watched.

Kostis is one of the most respected swing gurus.

He's also out of sorts with Butch Harmon, the swing guru he exiled nearly two years ago.

"Tiger is playing better than he ever has," his swing guru, Butch Harmon, said before his par 71 for a 10-stroke lead on Saturday.

Woods's swing guru, Butch Harmon, had asked Floyd's permission to hire Williams.

Personal instructors, often called swing gurus, are increasingly being accepted into the inner circles of the best players in the world.