TROON, Scotland — Phil Mickelson had turned back the clock for a fourth consecutive day. He had made a birdie on the opening hole of Sunday’s final round at the 2016 British Open and never looked back. His game was as sharp as it had ever been on the final day of a major championship. Winless for the past three years, the 46-year-old Mickelson was tied for the tournament lead, just five holes and perhaps one last surge from becoming the oldest British Open champion in 149 years.
And yet Mickelson felt as if nothing he was doing was enough to win. Or might ever be enough on this day.
Three birdies, an eagle and no bogeys in his first 13 holes?
Mickelson’s playing partner, Henrik Stenson, had not flinched at that run, rolling in dicey, spectacular and lengthy birdie putts from seemingly every quarter of the Royal Troon greens.
“I had to make 30- or 40-footers just to try to keep pace with him,” Mickelson later said.
The two of them went to the 15th green sizing up birdie putts, with Stenson’s ball 51 feet from the hole and just off the green.
“I had about a 40-footer on 15, and I’m thinking, ‘I’ve just got to make that,’” Mickelson said.
He was right, because Stenson improbably sank his monster putt. When Mickelson missed, Stenson had the edge he needed and ran with it. His ninth and 10th birdies in the closing three holes were only exclamation points on the way to a British Open title that made Stenson the first Swede to win a men’s major golf championship.
Stenson became the second golfer to win a major with a final round of 63, finishing three strokes ahead of Mickelson, whose six-under-par 65 was the lowest score he has posted in the final round of a major. Stenson’s score of 20 under par tied Jason Day’s record for the lowest winning score relative to par in a major, and Stenson’s aggregate four-day score of 264 was also a major championship record.
J. B. Holmes was the closest pursuer to Stenson and Mickelson, finishing in third place, a whopping 14 strokes behind the champion.
“I knew Phil wasn’t going to back down at any point, and in some ways, that made it easier for me because I knew I could never rest and had to keep making birdies,” said Stenson, who had twice finished tied for the third at the British Open and once was second, when Mickelson won the event in 2013.
But Stenson said he had entered this year’s tournament certain that his fortunes at major championships — he has four other career top-five finishes in majors — were finally going to turn.
“It’s not something you want to run around and shout,” he said. “But I really did feel like I was going all the way this week. I could feel my putting improving and leading me there.”
While Mickelson has a well-documented history of runner-up finishes in major championships, Stenson, the world’s sixth-ranked golfer, had also been in something of a slump until recently, with one win on the PGA or European tours since 2014 and multiple top-five and top-10 finishes.
Those near-misses may have been on Stenson’s mind when Sunday did not start auspiciously. He badly missed an eight-foot par putt to bogey the first hole. When Mickelson birdied that hole, he vaulted into the lead, eclipsing the one-shot third-round advantage Stenson had held overnight.
But with pluck, precision and a steely putting stroke under pressure, Stenson found the resolve missing in previous major championship finales. Stenson has always been known as a great ball striker, especially with his irons. If he has displayed a weakness, it has been on the greens, where short putts have especially bedeviled him in tense moments. But Sunday, he thrived.
Still, Stenson knew his reputation. As crucial as the long putt on the 15th green was, when Stenson was asked which situation made him the most nervous Sunday, he quickly mentioned a four-and-a-half-foot putt he faced on the par-5 16th hole. Mickelson had just made a birdie, and Stenson said it occurred to him as he stood over his short birdie putt that it was vital that he not give Mickelson any momentum heading into the final holes.
“That was the most pressure I felt,” he said. “Making that putt was huge.”
It mimicked many other moments when Stenson held off the charging Mickelson, who did not make a bogey Sunday.
Stenson made birdie putts of 12 and 15 feet on the second and third holes. When Mickelson eagled the fourth hole, Stenson made sure he remained tied for the lead with his third birdie in the first four holes.
The tie was briefly broken at the par-3 eighth hole, which is known as the Postage Stamp, when Mickelson’s tee shot was considerably inside Stenson’s, but it was Stenson who made a birdie putt, while Mickelson missed.
Mickelson pulled even again at the 11th hole, then made a spectacular par save after rescuing his ball from the fescue rough twice on the 12th hole. But Stenson charged ahead yet again on the 14th hole with his seventh birdie when he converted a 20-foot putt.
After Sunday’s trophy ceremony, Stenson courteously acknowledged that he grew annoyed having to repeatedly answer questions about why no male Swedish golfer had won a major championship.
“Many great players from my country tried in past decades, and there’s been a couple of really close calls,” he said.
He added that his countryman Jesper Parnevik, who was second at the British Open in 1994 and tied for second in 1997, had contacted him before Sunday’s final round.
“He sent me a message, ‘Go out and finish what I didn’t manage to finish,’” Stenson said. “And I’m really proud to have done that, and it’s going to be massive for golf in Sweden.”
Mickelson, meanwhile, remained disenchanted over falling short of winning his sixth major championship.
“It’s not like I have decades left of opportunities to win majors, so each one of these means a lot to me,” he said.
But as a close eyewitness to a historic final round, he knew better than anyone what had transpired at Royal Troon on Sunday.
“I played close to flawless golf and was beat,” Mickelson said. “It’s probably the best I’ve played and not won. But Henrik made 10 birdies, so what are you going to do?
“I like and respect him — it was impressive, and he’ll be a great champion.”
An earlier version of this article incorrectly stated Henrik Stenson’s margin of victory. He beat Phil Mickelson by three strokes, not two.