AUGUSTA, Ga. (AP) -- Bubba Watson wants to keep it simple.
None of those wild shots off the straw or from behind a tree.
Bubba golf? Not this time at the Masters.
Boring golf is more like it.
"It's not science here," Watson said. "It's try to hit the greens. And if you're hitting the greens, that means you're obviously hitting your tee shots well. So that's all I'm trying to do is just hit the greens ... maybe throw in a birdie here or there. That's what I've done the last two days and it's worked out so far."
If Watson can keep it going another two days, he'll be collecting his second green jacket Sunday evening.
The left-hander put up another round in the 60s on Friday, seizing control with a dazzling five-hole stretch on the back side at Augusta National, posting nothing but birdies from the 12th to the 16th. Watson was only the fifth player in Masters history to pull off that feat.
Even after missing a short putt and taking bogey at the 18th, he finished with a 4-under 68 for a three-stroke lead heading to the weekend.
The 7-under 137 provided the biggest 36-hole advantage at the Masters since Chad Campbell was up by three shots in 2006.
Watson hopes it works out better for him than it did for Campbell, who soared to a 75 on that Saturday eight years ago and wound up three shots behind winner Phil Mickelson.
"Just keep my head down, try not to focus on the crowds cheering for me and stuff," Watson said. "Trying to stay level, not too energized, not too excited."
When Watson captured his first green jacket two years ago, he memorably played a style dubbed "Bubba golf" -- raw skill and wild imagination, culminating with a memorable shot from far off the 10th fairway that beat Louis Oosthuizen in a playoff.
There was nothing outlandish about his birdie spree Friday, just brilliance and power on a demanding day of crispy greens and swirling wind. Watson had missed only eight greens the first two days. He's made only two bogeys in 36 holes.
"Bubba is tearing it up," said Jordan Spieth, the 20-year-old from Texas who doesn't look at all like an Augusta rookie, four strokes back after shooting 70. "So we've got to go get him."
There are plenty of players ready to give chase.
John Senden, who qualified for the Masters a month ago with his win at Innisbrook, was three shots behind. After a rugged start, he played the final 14 holes with six birdies and no bogeys for a 68 that puts him in the last group at a major on the weekend.
Defending champion Adam Scott also made a late recovery with three birdies on the back nine to salvage a 72, along with his hopes to join Tiger Woods, Nick Faldo and Jack Nicklaus as the only players to win back-to-back at Augusta.
Scott was at 141, joined by Spieth, Thomas Bjorn (68) and Jonas Blixt (71). There's also the ageless Fred Couples, who won the Masters a year before Spieth was born. Couples, cool as ever at 54, had another 71 and was five back.
Woods, who missed the Masters for the first time in 20 years because of back surgery, won't be the only guy watching on television. Phil Mickelson made another triple bogey -- three shots from the bunkers on the par-3 12th hole -- for a 73 and missed the cut for the first time since 1997. So did Sergio Garcia, Ernie Els, Luke Donald, Webb Simpson, Dustin Johnson and Jason Dufner.
Rory McIlroy nearly joined them. He hit one tee shot over the fourth green, past the head of Adam Scott on the fifth tee and into the bushes for a double bogey. Another shot hit a sprinkler head and landed in the azaleas behind the 13th green. He had to make a 4-foot par putt to make the cut at 4-over 148.
Watson seems further away from the field than just three shots.
But U.S. Open champion Justin Rose was not ready to give up, even from nine shots behind, because the leader often comes back to the field.
"There's no give on this golf course," he said. "The hole can start looking awfully small, and those lakes can start to look awfully big."
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