AUGUSTA, GA. – Friday was a bad day for swing coaches, personal trainers, workaholics and anybody who can't hit a 9-iron 186 yards without the help of a cart path and a strong breeze.

Friday was a bad day for the average Masters entrant, most of whom played Augusta National so defensively you wondered if they kept Mace in their bag, just to keep sport's greenest monster at bay.

At the Masters, Friday was a bad day if your name wasn't Bubba, you don't use a hillbilly doll dressed in overalls as your driver head cover and you can't hit the ball 370 while moving your feet like a septuagenarian learning the tango.

In the second round of the Masters, two years after he won his first and only major at Augusta, Bubba Watson went deep, smashing his driver improbable distances, shooting a 68 on a pretty-but-windy day, and revealing the emotional underpinnings of his greatest success and recent slump.

Bubba reprised everything he's famous for other than crying, and why would he cry after taking a three-shot lead at the Masters with a run of five consecutive birdies on the back nine?

"It's not science," Watson said, debunking an entire golf industry based on video lessons, swing prototypes, magazine tips, sports psychology and trampoline effects.

Golf instructors might shudder to watch Bubba Watson’s self-taught swing, but his length and creativity helped him to a 68 on Friday and the Masters lead.

It's never science with Watson, a self-taught golfer from a poor family in Bagdad, Fla., who plays by feel, took a long vacation from the game after his only major victory, and admits his practice sessions rarely last an hour.

Watson followed a bogey-free, opening-round 69 with a 68 on Friday, leaving him at 7 under for the tournament, three shots ahead of John Senden, then admitted his 2012 Masters victory sent him into a career funk that he seems to have greatly enjoyed.

"I was still celebrating my green jacket," he said, drawing laughter as he nodded to a questioner. "How many green jackets you got? If you had one, you would celebrate it for a year or two.

"You've got to think about where I've come from, my mom having two jobs to pay for my golf, my dad working in construction. And when you think about that and where I am in my career and where I am with my family, my young family …"

Here Watson paused, as if ready for his traditional news-conference cry … but then he swallowed, and continued. "You're thinking about how great this was," he said. "Besides the Lord, marrying my wife and having our child, it's right there, it's fourth or fifth on that list. So when you think about that, it's an accomplishment for a guy named Bubba."

If you ever forget his name, just look at his driver head cover, a hillbilly with one overall strap unbuttoned wearing a visor with his name emblazoned on it.

"My year, my career, was complete after that win," he said. "Obviously I was going to have a hangover. I've never been drunk before, but a hangover from the green jacket. You know, I do everything my way."

Yes, he does. Conventional golf instruction encourages a square, athletic setup, a limited backswing, elbows that remain close to the body, a smooth transition and solid footwork. Watson takes an open, narrow stance, brings the club back until it points at the ground in front of him, sticks his left elbow out like the dreaded chicken wing, then unleashes a motion so violent his feet slide around as if he's standing on ice.

With such a wide arc and so few inhibitions, he hits inconceivable drives and ozone-piercing iron shots. On the par-3 16th on Thursday, he hit his 9-iron 186 yards. "He's hitting wedges and sand wedges into a lot of holes and I'm hitting 6-iron," said playing partner Luke Donald. "When he's controlling his ball as well as he is right now, it's going to be tough to catch him."

Donald thinks Watson has another advantage: Being lefthanded, he's able to play a controlled fade instead of a draw into Augusta's fast greens. If Watson wins this weekend, six of the past 12 Masters would have been won by lefthanders Phil Mickelson (2004, 2006, 2010), Mike Weir (2003) and Watson.

Watson's view of that theory was typically unscientific. "Lefties," he said, "are the best."

Jim Souhan can be heard weekdays at noon and Sundays from 10 to noon on 1500 ESPN. His Twitter name is @SouhanStrib. jsouhan@startribune.com