AUGUSTA, Ga. — As Tiger Woods was making his stirring late charge up a bunched Masters leaderboard Friday, he was chasing a formidable cast of rivals that included six major golf championship winners.
Any one of them could have tripped up Woods’s run at the lead as the tournament reached its halfway point.
Instead, for one alarming moment, it appeared that a stumbling security official at Augusta National Golf Club might derail Woods’s most memorable Masters surge in years.
After Woods hit a shot out of the trees left of the 14th hole, a sprinting uniformed guard, who was trying to control the crowd just behind Woods, slipped on wet grass and slammed into Woods’s right ankle. Woods recoiled and limped forward, hopping on his left foot several times before regaining his footing.
But Woods, who grimaced but never looked back, kept striding toward the green. In fact, the episode seemed to spur him to greater heights.
With the galleries around him cheering wildly, Woods birdied the 14th and 15th holes, and he had two choice opportunities in the closing holes to vault into the lead. While those birdie putts slid past the hole, Woods still managed a four-under-par 68 and a two-day score of six under that left him a shot off the tournament lead shared by five golfers.
With a smile, Woods said: “Accidents happen, and you move on. I’ve had galleries run over me. When you play in front of a lot of people, things happen. But it’s all good.”
Woods insisted he was not injured in the accident, which looked a little like a base runner trying to take out an infielder at second on a double-play attempt.
When pressed on whether he was physically sound for the Masters’ weekend rounds, Woods grinned and answered: “Yeah, other than having four knee surgeries and four back surgeries, I’m fine. Good to go.”
On a day when most of the top scores were produced by golfers teeing off in the morning, with the sun out, Woods’s ascent up the leaderboard as an evening rainstorm drenched the golf course was something of a surprise.
At one point, it seemed the poor weather could undermine Woods, as play was suspended just after he hit his tee shot to the menacing 12th green, about 5 feet behind the hole.
When play resumed 29 minutes later, Woods, who admitted he grew stiff during the delay, missed the birdie putt. Then his short birdie putt on the 13th hole stopped an inch in front of the hole’s center. At the time, Woods was stuck at four under for the tournament.
“I had a few chances go the wrong way, but I wasn’t too bummed about it because I also hit a lot of really good shots,” Woods said later. “So I was still confident.”
Indeed, Woods was at his scrambling best, reaching 16 of 18 greens in regulation despite missing half of the fairways on the 14 par-4 and par-5 holes.
He missed a 7-foot birdie putt at the 17th hole and a 15-footer at the final hole. Converting either of them would have put him in a tie for the lead.
Afterward, Woods could not resist stressing that he has now been a contender in three consecutive major golf championships, including last year’s British Open and P.G.A. Championship.
“I felt very good out there doing what I was doing, and so now this is three straight majors that I’ve been in the mix,” he said. “So it’s good stuff.”
Most of the attention early Friday was on Molinari, which was unusual because he is rarely included in the featured groupings of top golfers selected by tournament officials. And even as Molinari was shooting a bogey-free 67, he toured Augusta National largely unrecognized.
But Molinari, the reigning British Open champion, the world’s seventh-ranked golfer and a winner just last month on the PGA Tour, does not seem perturbed by the disregard.
“There’s obviously loads of great players in golf right now; I think I’m getting the attention that I deserve,” said Molinari, who played Friday with Tyrrell Hatton and Rafa Cabrera-Bello. “So I’m happy to go about my business and keep playing good golf.”
Molinari’s climb into golf’s upper echelon, however, may soon be impossible to overlook, even on American soil.
Day also shot 67 as he moved into a tie for the lead. Koepka cooled off slightly after Thursday’s round of 66, shooting 71. Scott looked as if he would have the halfway lead all to himself until his putter let him down and he bogeyed the 16th hole. Oosthuizen, who often plays well at the Masters, charged with a 33 on the back nine.
Dustin Johnson, the world’s second-ranked golfer and another major champion, finished a stroke behind the leaders along with Justin Harding, a Masters rookie from South Africa.
In the end, it was Molinari who played the most consistently, making five birdies and 13 pars.
Molinari first participated in the Masters in 2006 as the caddie for his brother, Edoardo, who qualified as the United States Amateur champion. This is his eighth go-round as a player, and it has been an arduous process to make himself comfortable at Augusta National. Molinari is 24 over par in the 26 rounds he has played, and he has shot 75 or higher eight times, including an 81 in 2013.
Even caddying for his brother was “a bit of a nightmare,” Molinari said Friday.
“It’s not great fun to caddie around here,” he said. “I can tell you that. I loved being here, but it’s just so hard.”
Slowly, Molinari has acclimated. It has not hurt that he has played the best golf of his career in the last 14 months, including a star turn at the Ryder Cup in September. Over his last four rounds at Augusta National, Molinari is 10 under par.
Most of the improvement has been in his putting on the demanding Augusta National greens, which require a precise understanding of subtle contours and topography.
Asked to describe what he had done to become a better putter, Molinari snickered.
“I’ve changed pretty much everything that you can think of,” he said, explaining that he had altered his posture, putter path and tempo. He has also changed putters and putter shape.
Molinari said his putting overhaul could have been more sweeping only if he switched from a right-handed stance to a left-handed one. He needed just 25 putts on Friday as he moved into a share of the lead.
“There’s a long way to go yet, but I’m happy and doing better than in the past here,” he said. “Hopefully I can keep doing the same.”
The world’s top-ranked player, Justin Rose, shot four over through Friday and missed the cut.
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