AUGUSTA, Ga. -- It might be a little too early to say Bubba Watson is running away with the 78th Masters.
But, with such little star power behind him on the leader board, it might be a good idea if he does.
With Tiger Woods already missing from the first major of the season and Phil Mickelson not playing on the weekend for the first time in 17 years, the Augusta National Golf Club is going to need someone to keep its tournament from becoming the Valspar Championship.
And that would be Watson, who had the hills rattling and the pines shaking Friday with a back-nine birdie binge that has him honing in on his second green jacket in three years.
Run, Bubba, run.
"You can see why he's had some success around here," said England's Luke Donald, who played with Watson for two rounds and is among the number of big-name players to miss the cut.
"He's hitting wedge and sand wedge into a lot of holes and I'm hitting 6-iron, so it's a big advantage. And he spins his irons a tremendous amount with the greens getting get firmer and firmer. When he's controlling his ball as well as he is right now, it's going to be tough to catch him if he keeps playing like that."
Watson tied for the low round of the day with a 68 that left him at 7-under 137, three shots ahead of Australian John Senden and four shots clear of defending champion Adam Scott.
After posting the only bogey-free score in the opening round, Watson vaulted to the top of the leader board when he made five consecutive birdies, beginning at No. 12. The assault was mindful of the charge he put on in the final round in 2012 when he made four consecutive birdies on the back nine en route to his stunning playoff victory.
"The four straight birdies I had a couple years ago felt a lot better," Watson said. "It's one of those things, every guy in the field has had that stretch before, playing with their buddies or playing in a tournament, so it's not that big a deal when we think about it. But, at the Masters, it makes it a big deal."
Watson made only two mistakes: Missing the green at No. 9 to make his first bogey in 27 holes; and missing the green at the final hole for only his second bogey in two days. Just as impressive, he hasn't had a three-putt green in two days, not bad for a self-described jittery putter.
"Not only the back nine, I thought he played great all day," said Spain's Sergio Garcia, who played with Watson. "He drove the ball really, really good, very far. His iron play was extremely good. He played extremely well throughout the whole two rounds. That's why he is where he is."
The closest pursuer is Senden, who won his first PGA Tour title a month ago at the Valspar Championship and closed with a bogey-free 33 on the back that moved him within three shots of the lead. Senden is at 140.
"The secret of this course, I think, is keeping the big numbers off the card," said Senden, who settled down after two bogeys in the first four holes to shoot 68. "That kind of puts you straight out of contention. And if you can do that well you have a chance."
Scott, who began the second round with three bogeys in the first five holes, needed a back-nine rally to finish at 141. And he got it with three birdies in a four-hole stretch at Nos. 12, 13 and 15. That left him tied with young Jordan Spieth, Thomas Bjorn of Denmark and Jonas Blixt of Sweden.
Scott is actually in better position after two rounds than he was a year ago when he was tied for seventh heading into the weekend.
"It's good to be within shouting distance," Scott said. "[Saturday] is a big day for everyone. I'd like to close that gap and feel like on Sunday I have a chance."
Spieth, 20, is appearing in his first Masters and has a chance to become the youngest winner in tournament history. But he will need more shots like the eagle-3 he made at No. 15 and the 3-foot birdie he made at the finishing hole to challenge Watson.
"This was a big goal of mine this year to get in contention at a major," Spieth said. "The Masters being the one that I dreamt about since I was who knows how old, that's going to leave more emotion out there."
Then there is former Masters champion Fred Couples, doing what he always seems to do at Augusta National -- hanging around the lead. He is at 2-under 142, tied with Jim Furyk and PGA Tour money leader Jimmy Walker.
It is the fifth year in a row Couples has been among the top 10 heading into the weekend at the Masters. But, in the past three years, his scoring average on Saturday is 74.6.
"I say the same thing every year -- I feel great about playing here," Couples said. "And when you see me in the parking lot Saturday night I'm all dejected. I haven't been able to keep putting these rounds together."
Ten years after he won the first of his three green jackets, Mickelson missed the cut for the first time since 1997 after shooting 73 to finish at 149. For the second day in a row, he made a triple bogey without incurring a penalty stroke, this time making 6 at the par-3 12th when he went from the front bunker to the back bunker back to the front bunker.
Among the other players missing the cut were Garcia, Dustin Johnson, four-time major champion Ernie Els, reigning PGA champ Jason Dufner, former U.S. Open champ Graeme McDowell and four Masters champions from the past seven years -- Zach Johnson, Charl Schwartzel, Trevor Immelman and Angel Cabrera.
"That's what I've been nervous about," Mickelson said. "That's the kind of stuff when you're playing tournament golf and you're mentally sharp you don't do. And that's the kind of stuff I seem to be doing right now."
Gerry Dulac: firstname.lastname@example.org and Twitter @gerrydulac.