Jason Anthony Day (born 12 November 1987) is an Australian professional golfer. Day had early success as a professional, earning PGA Tour membership in his teens. In his third season, he won the HP Byron Nelson Championship and recorded runner-up finishes at the Masters and U.S. Open. In 2015, Day recorded his breakout season, winning five events including the PGA Championship, a major championship, while ascending to #1 in the world. Day maintained exemplary play through 2016, winning The Players Championship and preserving his #1 ranking. Since that season, however, Day's play has been much more erratic and he ultimately fell outside of the top 100 in the world. In 2023, however, he recorded a comeback year, winning the AT&T Byron Nelson, the site of his first win, and returning to the world's top 20.
