Jon Rahm is a major champion for the first time.

Rahm overtook Louis Oosthuizen down the stretch to win the 2021 U.S. Open at Torrey Pines Golf Course in San Diego, California. He went four under in the final round to finish at six under for the tournament, one shot better than Oosthuizen.

U.S. Open Leaderboard

1. Jon Rahm (-6)

2. Louis Oosthuizen (-5)

3. Harris English (-3)

T4. Guido Migliozzi (-2)

T4. Brooks Koepka (-2)

T4. Collin Morikawa (-2)

T7. Branden Grace (-1)

T7. Daniel Berger (-1)

T7. Paul Casey (-1)

T7. Xander Schauffele (-1)

T7. Scottie Scheffler (-1)

T7. Rory McIlroy (-1)

Full leaderboard available at USOpen.com

With Oosthuizen failing to distance himself from the pack, Rahm continued to knock on the door but couldn't catch up with the South African. A long birdie putt on No. 15 had the right line but was hit with too much power and lipped out. Another birdie putt on No. 16 didn't break enough and resulted in a par.

Rahm's luck finally turned around on No. 17. He was on the money with a 25-foot birdie putt to get to five under and tie Oosthuizen for the lead.

The par-five 18th hole was a case of deja vu.

Rahm put his approach in the bunker, hurting his odds of earning a pivotal birdie before heading for the clubhouse. He opted for the safe approach to get onto the green, which still left him 18 feet away from the cup. That didn't prove to be a problem for the 26-year-old Spaniard.

Rahm was still left waiting, though, as Oosthuizen finished up his round.

During the first three rounds, Oosthuizen had five birdies and an eagle between Nos. 16 and 18, but the tournament was far from over to that point.

In the final round, he under-hit a birdie putt on No. 16 to settle for par and then sliced his drive on No. 17 into the penalty area to the left of the rough. After a one-shot penalty, Oosthuizen got onto the green with his third shot but rolled his par putt to the right of the cup.

The 2015 U.S. Open runner-up eagled No. 18 on Saturday. He couldn't get lightning to strike twice Sunday.

It appeared the 2021 edition was shaping up to be one of the most dramatic U.S. Opens ever. At one point, 10 golfers were within one shot of the lead.

Then, the contenders quickly began to fall by the wayside.

Brooks Koepka leveled off following a fast start in the final round. He made the turn at three under, raising hopes of a head-to-head battle with Bryson DeChambeau. Koepka's momentum stalled on the back nine thanks to a pair of bogeys. He watched his birdie roll just left of the cup on No. 17. A par left him stuck at three under with little chance of challenging for the lead.

DeChambeau's quest for a repeat came to an end on the 13th hole.

He was already heading in the wrong direction with bogeys on Nos. 11 and 12. On his way to a double bogey on No. 13, he saw his ball come to a rest next to an empty box of Stella Artois.

The 13th hole also claimed Collin Morikawa, who walked to the tee box at four under and walked off the green at two under.

Mackenzie Hughes was tied at five under with Oosthuizen and Russell Henley atop the leaderboard through 54 holes. One shot summed up how his day unfolded.

The 30-year-old Canadian hooked his tee shot on No. 11. The ball bounced off the cart path and into a tree to the left of the green, where it got stuck.

Richard Bland was the tournament's biggest surprise at the halfway mark, holding a share of the lead with Henley. A six-over 77 in the third round doomed his chances of winning, and his slide continued Sunday. Bland tumbled further after carding a seven-over 78 to finish at eight over for the tournament.

Henley had three straight bogeys before making the turn to No. 10 en route to a five-over round.

As the U.S. Open wound toward its conclusion, it seemed fair to wonder if anybody actually wanted to win the thing.

That made Rahm's finishing kick stand out even more. He remained composed and didn't get frustrated when he was unable to chase down Oosthuizen. He lived up to his status as the betting favorite heading into the event.

The Travelers Championship at TPC River Highlands in Cromwell, Connecticut, is the next stop on the PGA Tour.

Rahm was in position to cruise to victory in the Memorial Tournament before he tested positive for COVID-19 and had to withdraw. Given his current form, a win in the Travelers might be on the table if he makes the trip eastward.