U.S. Open 2015: Jordan Spieth claims back-to-back majors in dramatic finale

CNN  — 

Masters champion Jordan Spieth kept his nerve to claim the U.S. Open title Sunday in a dramatic finish at Chambers Bay.

Spieth had birdied the final hole to finish on five-under 275, but then watched as fellow American Dustin Johnson three-putted from 12 feet on the 18th to finish one shot behind, tied with South African Louis Oosthuizen for second.

Johnson’s eagle putt for outright victory on the par-five closing hole went adrift, and he then missed the short four-foot birdie putt which would have forced a playoff on Monday.

The 21-year-old Spieth is the youngest U.S. Open champion since Bobby Jones in 1923 and only the sixth man in history to win this title and the Masters in the same year, Tiger Woods being the last in 2002.

He is now halfway to the grand slam, with the British Open at St. Andrews and U.S. PGA Championship to come later in the year.

“I feel for Dustin,” Spieth said. “I’m still amazed that I won, let alone that we weren’t playing tomorrow.

“We’re going to go to St. Andrews looking for the Claret Jug. I believe we can get it done if we get the right prep in,” he added.

Oosthuizen challenges

Former British Open champion Oosthuizen charged through the back nine in 29 shots for a 67 to set a testing clubhouse target of four-under 276.

Joint overnight leader Branden Grace, tied in the lead with Spieth at five-under playing the 16th, made a double bogey to end his hopes and the eventual champion pulled three shots clear as he birdied.

But Spieth then showed his first signs of fallibility by making an ugly double bogey five on the short 17th, before recovering with a battling birdie on the 18th.

Australian Jason Day, so brave in fighting off vertigo in rounds two and three, fell away to finish on level par after starting the final round tied with Spieth, Johnson and Grace on four-under.

McIlroy charge

Two earlier starters had threatened to turn the tournament on its head, with world number one Rory McIlroy moving to two-under-par when he rolled home a monster 72-foot birdie putt on the 13th.

It took the Northern Irishman to six-under for the day, but he missed a short birdie opportunity on the next and then frittered two shots away to close with a 66 and level par.

Aside from McIlroy, an even bigger threat emerged as former Masters champion Adam Scott, with Woods’ old caddy Steve Williams on his bag, was quietly moving up the leaderboard.

When he birdied the final hole for a best-of-the-week 64, Scott had set a challenging three-under 277 total, good enough for a tie for fourth with South African Grace and fellow Australian Cameron Smith.