In 2008, Fowler repeated as Sunnehanna Amateur champion. In the first round of the U.S. Open, Fowler shot a −1 (70) and was in a tie for 7th place. He was one of three amateurs to make the cut, along with Derek Fathauer and Michael Thompson. He ended the tournament tied for 60th. In October 2008 Fowler played on the Eisenhower Trophy team that finished second. He was the leading individual player.
BMW Championship: At No. 22 in the FedExCup standings heading into the third Playoffs event, the BMW Championship, he bogeyed No. 17 in a final-round even-par 72 to miss advancing to the TOUR Championship by half a point, finishing the season No. 31 in the FedExCup standings. Charl Schwartzel fired a final-round 8-under 64 to claim the No. 30 position.
Lowry did not win on the European Tour from 2016 to 2018 but was joint runner-up in the 2017 DP World Tour Championship, Dubai and runner-up in the 2018 Andalucía Valderrama Masters. In January 2019 he won the Abu Dhabi HSBC Championship by a stroke from Richard Sterne. Lowry led by 3 strokes after three rounds but was two-over-par after 11 holes of his final round and dropped 4 shots behind Sterne. However he finished with 3 birdies in the final 7 holes, while Sterne had two bogeys, giving Lowry the victory.
Lowry started the 2018-19 season with partial status after finishing 140th in the FedEx Cup. He moved into a share of the 36-hole lead at the 2019 Open Championship at Royal Portrush, after successive opening rounds of 67. He was tied at eight under with J. B. Holmes. Lowry then shot a 63 for a new course record to lead by four strokes at the end of the third round. He won the tournament by six shots ahead of Tommy Fleetwood.
After a T-12 finish at the Masters, Fowler earned his first win in over three years with a playoff victory at The Players Championship in May. Trailing Sergio García midway through the final round by five shots, Fowler played the final six holes in 6-under par, including an eagle at the par-5 16th. After a birdie at the famous 17th hole, Fowler's final birdie of the round on 18 left him at 12-under par. Both García and Kevin Kisner had birdie attempts to win at the 18th in regulation, but both missed and the three men went to a three-hole aggregate playoff to decide a winner on holes 16–18. Fowler and Kisner went par-birdie-par to tie at −1 while García's three pars left him at even and he was eliminated. Thus Fowler and Kisner went to sudden death starting at the 17th, where Kisner's tee shot landed within about 12 feet (3.7 m) of the cup. Fowler answered with a shot inside of five feet, and when Kisner's birdie attempt slid by, Fowler responded by making his short birdie to claim the championship. Fowler played his final 10 holes in 8-under par. On July 12, he won the Aberdeen Asset Management Scottish Open on the European Tour, shooting a 12-under-par 268. On September 7, he won the Deutsche Bank Championship, the second FedEx Cup Playoffs event, by one stroke over Henrik Stenson, for his third victory on the PGA Tour.
The Honda Classic: After beginning the final round of The Honda Classic with a four-stroke lead, posted a 1-over 71 to win by the same margin for his fourth career PGA TOUR title. It marked the first of five 54-hole leads he converted to victory. Opened with back-to-back 66s for the second consecutive year and posted a 65 in the third round to post the best 54-hole total since the event moved to PGA National in 2007 at 13-under 197. Seized the 54-hole lead with the widest margin of his career entering a final round. Turned in 2-over 37, but posted three birdies on the back nine to take command of the tournament. Despite bogeys on the 71st and 72nd holes, claimed his first victory since the 2015 Dell Technologies Championship. Finished the week second in Strokes Gained: Putting (7.392) and moved to 10th in the FedExCup standings and ninth in the Official World Golf Ranking, his first time in the top 10 since the 2016 BMW Championship.
PGA Championship: Finished T3 and two strokes behind McIlroy at the PGA Championship in his 20th major championship start, with T19 in 2013 the previous-best finish in four prior PGA Championship starts. Became the first to claim top-five finishes in all four majors since Woods in 2005. Since 1934, is just the third player to perform the feat, joining Woods in 2000 and 2005 and Jack Nicklaus in 1971 and 1973. Played all four majors in 32-under, with McIlroy second on the list, at 27-under.
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).
Lowry missed the first three cuts of his professional career, but had his first payday on 5 July, when he finished 50th at the Open de France ALSTOM. He had his best professional result in November 2009, when he finished 3rd in the Dunlop Phoenix Tournament in Japan. In January 2010, Lowry finished in fourth place in the Abu Dhabi Golf Championship, moving him into the top-100 of the Official World Golf Ranking.
Fowler has three tattoos. One is a block "G" near his left elbow in honor of Georgia Veach, the daughter of a Seattle pastor and friend. Georgia was diagnosed with lissencephaly. Fowler got the tattoo just before the 2015 Presidents Cup. The second is from January 2016 and contains the name Yutaka Tanaka (Rickie's grandfather) in Japanese script on his left biceps. The third tattoo came just weeks after playing at the 2016 Summer Olympics and is of the Olympic symbols.
The form and fitness of centre-backs Michael Morrison and Jonathan Spector and left-back Jonathan Grounds restricted Lowry to a seat on the bench until mid-December. He eventually made his debut in the starting eleven for the home fixture against Cardiff City on 18 December, standing in for the injured Grounds at left back. He appeared once more, in the FA Cup, before his contract was cancelled by mutual consent to enable him to return to Australia.
All of DeChambeau's irons and wedges are cut to exactly the same length: 37.5 inches (95.3 cm). Their lie and bounce angle are also the same; only the lofts are different. In addition to the single-length concept, his clubs are unusual for their extremely upright lie angle.  DeChambeau keeps the club on the same plane throughout his swing and does not turn his wrists during his swing. In 2011, at the suggestion of his instructor Mike Schy, DeChambeau switched to JumboMax Grips, the largest grips commercially available. The larger grips allow DeChambeau to hold the grips in his palms and not his fingers.
THE PLAYERS Championship: After beginning the final round of THE PLAYERS Championship three strokes off the lead, at 7-under 209, played his last six holes in 6-under to post a 6-under 66 and join a three-hole aggregate playoff with 2008 PLAYERS champion Sergio Garcia and Kevin Kisner. Finished birdie-par-birdie-eagle-birdie-birdie on Nos. 13-18 in regulation. Played Nos. 15-18 in a 5-under total of 11 strokes. The four-hole score of 11 set a new single-round low for the final four holes at TPC Sawgrass. Previously, seven players had finished with a score of 12 on the final four holes. When Garcia was eliminated after the aggregate playoff, Fowler and Kisner returned to the famed, par-3 17th for sudden death. Fowler converted a 4-foot, 8-inch putt for birdie to claim the title. Before his back-nine charge, his mother had made her way to the airport to leave town. A text message alerting her to her son's rally resulted in her immediate return to TPC Sawgrass in time to witness the win. With the victory, moved to ninth in the Official World Golf Ranking and No. 7 in The Presidents Cup standings.
On 27 January 2016, Lowry returned to Australia after a decade away from Australia when he signed a two-and-a-half-year deal with A-League side Perth Glory. Upon joining Perth Glory, Lowry said of the move, quoting: "I've got a lot of experience behind me now and I want to use it to guide the young lads who are in this young squad. I've spent 11 years in England and it's shaped my football over there and I'm really happy to be here and get stuck into the games"