In June 2015, he became the first SMU Mustang to win the NCAA individual championship, recording a score of 280 (−8) to win by one stroke. In August, he won the U.S. Amateur title, defeating Derek Bard 7 & 6 in the 36-hole final. He became the fifth player to win both the NCAA and U.S. Amateur titles in the same year, joining Jack Nicklaus (1961), Phil Mickelson (1990), Tiger Woods (1996), and Ryan Moore (2004).
Fowler's first PGA Tour event as a professional was the Justin Timberlake Shriners Hospitals for Children Open where he finished tied for seventh. His second PGA Tour event was at the Frys.com Open played at Grayhawk Golf Club in Scottsdale, Arizona. He finished tied for second after losing to Troy Matteson in a three-way playoff that included Jamie Lovemark. Fowler's score of 18-under-par included a hole-in-one on the fifth hole in his final round. Fowler also notched an eagle in each of his four rounds.
On June 16, Fowler carded a round of 65 at Erin Hills to take the first round lead at the 2017 U.S. Open. Fowler equaled the lowest first round score at the U.S. Open and led by one stroke from Paul Casey and Xander Schauffele. He followed this up with a one over par 73 in the second round to fall out of the lead by one stroke, held by four other players. He shot 68-72 over the weekend to finish in a tie for fifth place. This gave Fowler his sixth top-5 finish in a major, but he is still yet to win. Fowler started the PGA Championship with a 2-under 69 which was two strokes behind the leaders. After rounds of 70-73, he closed out the year's last major with a 4-under 67, including a run of four consecutive birdies on holes 12 through 15. Despite his solid finish, Fowler ended up tied for fifth and was 3 strokes behind the winner, and friend, Justin Thomas. It was his seventh top-5 major finish, meaning he's had multiple top-5 finishes at every major.
After Lowry's loan spell at Leeds was coming to an end, on 11 May he signed a new two-year contract extension at Aston Villa. It was a remarkable few days for Lowry, he was promoted with Leeds, received a call up to Australia's World Cup Squad and on the same day he signed a new two-year deal with Villa. Despite signing a contract with the club, Leeds United was considering re-signing him for the second time ahead of the 2010–11 season, but never happened.
The Barclays: Held a one-stroke lead over Patrick Reed after 54 holes at The Barclays in the FedExCup Playoffs, before a double bogey-birdie-bogey finish on Nos. 16-18 resulted in a T7 at 6-under 278 with Jason Kokrak and Ryan Moore. Fowler went bogey free at Bethpage Black from the 10th hole in round one until the 11th hole in the final round, a span of 55 holes. His 55-consecutive holes without a bogey became a personal best on the PGA TOUR, besting 53 from the 2010 Memorial Tournament. This streak also marked the longest recorded in Barclays history since hole information began in 1983. Ian Poulter had the longest with 45 in 2010. The finish marked his third top-10 showing in his last four starts in the event (T9/2013, T9/2014).