Robert Tyre Jones Jr. (March 17, 1902 - December 18, 1971) was an American amateur golfer who was one of the most influential figures in the history of the sport; he was also a lawyer by profession. Jones founded and helped design the Augusta National Golf Club, and co-founded the Masters Tournament. The innovations that he introduced at the Masters have been copied by virtually every professional golf tournament in the world. Jones was the most successful amateur golfer ever to compete at a national and international level.

Jones was not only a consummately skilled golfer but exemplified the principles of sportsmanship and fair play. In the first round of the 1925 U.S. Open at the Worcester Country Club near Boston, his approach shot to the 11th hole's elevated green fell short into the deep rough of the embankment. As he took his stance to pitch onto the green, the head of his club brushed the grass and caused a slight movement of the ball. He took the shot, then informed his playing partner Walter Hagen and the USGA official covering their match that he was calling a penalty on himself. Hagen was unable to talk him out of it, and they continued play. After the round and before he signed his scorecard, officials argued with Jones but he insisted that he had violated Rule 18, moving a ball at rest after address, and took a 77 instead of the 76 he otherwise would have carded. Jones' self-imposed one-stroke penalty eventually cost him the win by a stroke in regulation, necessitating a playoff, which he then lost. Although praised by many sports writers for his gesture, Jones was reported to have said, "You might as well praise me for not robbing banks."  A similar event occurred in the next U.S. Open, played at the Scioto Country Club in Columbus, Ohio. In the second round, after his opening round put him in second place, Jones was putting on the 15th green in the face of a strong wind. After grounding his putter during address to square up the club face, the ball rolled a half turn in the wind when Jones lifted the club head to place it behind the ball. Although no one else observed this movement of the ball either, again Jones called a penalty on himself, but this time Jones went on to win the tournament, the second of his four U.S. Open victories.  The USGA's sportsmanship award is named the Bob Jones Award in his honor.

Using a quote from the above article, answer the following question: What was he most well known for?
Jones was not only a consummately skilled golfer but exemplified the principles of sportsmanship and fair play.