Watch: Jordan Spieth Makes Eagle On 15th Hole And More Highlights From British Open Win

Jordan Spieth finished with a one-under-par-69 and posted a 72-hole score of 12-under 268 at the 146th British Open in Southport, England, on Sunday for his third major title.

Jordan Spieth NEWS: British Open highlights

The 23-year-old Dallas, Texas, native held a three-stroke lead in the final round of the tournament at Royal Birkdale. By the time he reached hole No. 13 on Sunday, that advantage had disappeared and Spieth — who won both the Masters and U.S. Open in 2015 — was tied with playing partner Matt Kuchar at 69.

By that point, Spieth was beginning to feel as concerned as he had felt in the 2016 Masters, where he blew a five-stroke lead in the last nine holes. The young American recorded a bogey on the par-4 13th after hitting a tee shot on the hole that ended up 40 yards to the right of the fairway and landed in high, thick grass, which forced him to take a penalty drop.

Spieth almost aced the par-3 14th, and then made one of his most incredible shots of the final round when he sank a 48-footer for an eagle on the par-5 15th to regain his lead over Kuchar by one shot.

Spieth and Kuchar both missed the fairway on the 17th, although the two players then also rebounded with birdie putts to retain a two-stroke difference before the 18th.

On the final hole, Spieth played it safe with his tee shot. His second stroke preceded a long birdie putt, and after Kuchar’s second shot landed in the bunker, Spieth made a par putt to seal his victory.

Spieth, 23, is now the youngest American to capture the British Open and the youngest champion overall since late Spaniard Seve Ballesteros in 1979. Spieth is also the second-youngest golfer after 18-time major champion Jack Nicklaus to secure three different major trophies.  Tiger Woods accomplished this at 24 and Rory McIlroy at 25.

“Closing today was extremely important for the way I look at myself,” said Spieth, who is also the only player to win 11 PGA Tour titles before the age of 24. He is now one PGA Championship title away from becoming the sixth man to complete a career Grand Slam, joining Gene Sarazen, Ben Hogan, Gary Player, Nicklaus and Woods.

“Growing up playing golf, I just wanted to be able to play in major championships and compete with the best in the world, and things have happened very quickly,” said Spieth. “And it’s good and bad, because a lot comes with it. And a lot more attention versus just being able to kind of go about your own thing. And I never realized how underrated that was. I wanted to be in this position but then, it becomes harder when it doesn’t go your way. And you’re harder on yourself because you expect so much. Therefore, I’m going to thoroughly enjoy this.”

Zach Johnson, the 2015 British Open champion, was completely stunned by Spieth’s performance on Sunday.

“Words fail me,” Johnson said. “I can’t fathom it. Those are the intangibles, and the things I just don’t understand. I’m not suggesting I can’t do it. He just does it all the time.”

Spieth — who has jumped from third to second in the official world golf rankings behind only Dustin Johnson — is now the favorite to win this year’s 99th PGA Championship, which will begin at Quail Hollow in Charlotte, North Carolina on August 10. According to Las Vegas SuperBook, Spieth and McIlroy are both favored to win the PGA Championship (and thus also record a career Grand Slam) with 8-1 odds.

SOUTHPORT, ENGLAND – JULY 23: Jordan Spieth of the United States celebrates victory after the winning putt on the 18th green during the final round of the 146th Open Championship at Royal Birkdale on July 23, 2017 in Southport, England. (Photo by Christian Petersen/Getty Images)