Jordan Niebrugge of the U.S. watches his tee shot on the fifth hole during the first round of the British Open golf championship on the Old Course in St. Andrews, Scotland, July 16, 2015. Reuters

Jordan Niebrugge had a record-setting day on Thursday, tying the mark for the lowest amateur round ever at a British Open held at St. Andrews’ Old Course in Scotland. The even-keeled 21-year-old coolly shot a 67, leaving himself near the top of the leaderboard.

The 2015 British Open, one of golf's four major tournaments, began at St. Andrew's on Thursday. Niebrugge is one of the few amateurs who earned a chance to play at the major by winning a qualifier. Before the tournament started, Niebrugge seemed confident about his prospects in interviews with International Business Times.

"My game feels great. My ball striking has really come along," he wrote in an email from St. Andrews. "I still need to get used to putting and how the surface may change each day depending on the moisture."

His putting seemed fine on his record-setting day, as Niebrugge rattled home a clutch birdie putt on No. 18 to tie the amateur record. In a phone call before heading out to Scotland, Niebrugge was excited by the prospect of playing the Open at perhaps the world's most famous course, but the rising-senior at Oklahoma State University took a workmanlike approach to the weekend.

"There's not much difference in the way I prepare for this tournament than an average college tournament," Niebrugge said in an email. "The only thing that may be different is the time I spend on the course."

Niegbrugge qualified for the Open after tying for first in a tournament in Southport, England, but this weekend is not his first appearance on golf's major stage. He also played the 2014 Masters after qualifying by winning the U.S. Public Links Championship.

In the lead-up to his opening tee time early Thursday morning -- 7:27 a.m. local time or 2:27 a.m. ET -- Niebrugge played more than four rounds on the Old Course. The comfort with the legendary loop showed on Niebrugge's opening scorecard. He knocked in seven birdies, and bogeyed just twice along the way to his five-under 67. While the first day of the British Open is still ongoing, Niebrugge has remained near the top of the leaderboard among famous names like Jordan Spieth and Dustin Johnson.

Niebrugge spent about three weeks in Europe earlier this summer in preparation for his second shot at a major. As the big tournament approached, he landed in Scotland at about 4 a.m. local time on July 10. Niebrugge got to work the next day, playing a practice round. On Monday, he got to hit the links alongside legend Tom Watson, who is making his final appearance at a British Open more than 30 years after his stunning loss to the late Seve Ballesteros at St. Andrews.

"It was a great experience playing with Tom Watson," Niebrugge said, but he quickly got back to business as usual. "After the round, I practiced more on what I needed to work on."

Tom Watson (2nd R) of the U.S. with Jordan Niebrugge of the U.S. during a practice round ahead of the British Open golf championship on the Old Course in St. Andrews, Scotland, July 13, 2015. Reuters

Niebrugge is playing sterling golf on the Old Course while most of his peers are likely toiling away as interns or working summer jobs. The novelty of that experience isn't lost on Niebrugge, who called the town "awesome." Before the tournament he spent time at local haunts with family, who traveled with him for the trip. His mother, father and sister all came along.

"It means a lot to me that all my family made the trip over here to support me," Niebrugge said. "They've been there every step of the way and I couldn't this without them."

Niebrugge will likely finish near the top of the leaderboard on Thursday. In his last major appearance, the up-and-coming golfer missed the cut at the 2014 Masters. His second major is looking quite different. While nothing is guaranteed, with a decent round Friday Niebrugge will likely earn the chance to play high-pressure weekend golf at the 2015 British Open. It'll be just another stunning experience for a golfer who has played majors at the world's two most famous courses. And that’s all before turning 22.