Jason Anthony Day is an Australian professional golfer. Day had early success as a professional, earning PGA Tour membership in his teens and winning an event in his third season, the HP Byron Nelson Championship. 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 three tournaments including 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.