In the history of modern professional golf, it has been exceedingly rare for a player to win a major championship in their first-ever appearance in a major -- as an amateur or professional.
Since the creation of the Masters Tournament in 1934, there are two players who won a men's major championship in their first start.
Ben Curtis won the 2003 British Open Championship at Royal St. George's in England, breaking through in his first-ever major start. When he won the claret jug, Curtis also won on the PGA Tour for the first time in his career. He wound up winning four times in total during his PGA Tour career.
Keegan Bradley won the 2011 PGA Championship at Atlanta Athletic Club in his first major appearance, winning in a three-hole playoff against Jason Dufner to capture the title. Bradley had won the HP Byron Nelson Championship earlier in the season to make the PGA Championship win his second of that spectacular year. He was also the first player to win a major using a long putter. He is still active on the PGA Tour and winning tournaments.
Francis Ouimet is the only other player to win a major championship in their first appearance that wasn't playing in the first edition of the tournament. Then 20 years old, Ouimet famously won the 1913 US Open, beating Harry Vardon and Ted Ray in an 18-hole playoff at The Country Club in Brookline, Mass. Ouimet went on the win the 1914 and 1931 US Amateur titles, which were considered major championships at the time.
Ludvig Aberg can join that rare company with a win in the 2024 Masters Tournament. He would also become the fourth golfer ever to win the Masters in their first appearance, following Horton Smith winning the first Masters in 1934 Gene Sarazen who won in 1935 and Fuzzy Zoeller who won in 1979 on debut.
