With this win, he entered the Official World Golf Ranking as an amateur at No. 168 and reached a career high of sixth in the World Amateur Golf Ranking. Walker Cup captain Colin Dagleish described the win as "fairytale stuff", adding: "You'd have to say that Shane's victory was the biggest (of the three amateur wins). To win your own national Open is quite something. It was unbelievable, it really was." The win was only the second home victory since 1982 and the first since Pádraig Harrington in 2007. Harrington himself was also full of praise: "It's fabulous for Irish golf. You only have to look at the fact it is such a rarity for an amateur to win, such a rarity for an Irish player to win the Irish Open. So, on a lot of fronts, it is a big deal. It was very impressive."
On July 16, 2017, DeChambeau earned his first PGA Tour victory by winning the John Deere Classic by a single stroke over Patrick Rodgers. He carded a round of 65 in the final round to win his maiden title in his 40th start on tour. The win coming the week before, gained DeChambeau a place in the 2017 Open Championship, where he missed the cut after rounds of 76–77 (+13).
Lowry made his debut for the Glory on 30 January 2016, starting against Melbourne Victory. Lowry then scored his first Perth Glory goal on 20 February 2016 when he scored a header in the 41st minutes, to give Brisbane Roar a thrashing with a 6–3 win for Perth Glory. Throughout the 2015–16 season, Lowry established himself in the starting eleven and formed a central defense partnership with Alex Grant, as he made ten appearance for Perth Glory in his first half of the season.
BMW Championship: After entering the final round of the BMW Championship in a second-place tie with Jason Day (five strokes behind Marc Leishman), recorded a 4-under 67 to finish T2, his 11th career runner-up on the PGA TOUR. Week was highlighted by a career-best, six consecutive birdies in the first round on Nos. 12-17. Chipped in from 64 feet on the 17th.
On August 26, 2018, he won The Northern Trust for his first playoff victory; in the process, he established a new record for the tournament when held at the Ridgewood Country Club, with a score of 266, besting the old Ridgewood record of 270, which was set in 2014 by Hunter Mahan. The following week, he won at the Dell Technologies Championship played at TPC Boston in Norton, Massachusetts, with a final score of −16, two shots clear of Justin Rose. This put him over 2000 points ahead of the second place player, Dustin Johnson, in the FedEx Cup rankings. This margin secured him top seeding at The Tour Championship, regardless of his finish at the BMW Championship. This also marked his fourth win on tour, third for the year, and second during the playoffs. At the Tour Championship, DeChambeau finished 19th out of 30 participants. As a result, he fell to 3rd in the FedEx Cup, winning $2,000,000.
Nationwide Tour Players Cup: Playoff runner-up to Derek Lamely at the Nationwide Children's Hospital Invitational. Started the final round five shots behind 54-hole leader Dave Schultz. Held the lead during much of the final round but suffered a bogey at the 72nd hole of regulation to drop into a tie with Lamely and force a playoff. Lost to Lamely when he failed to get up and down from a greenside bunker on the second extra hole, missing his par putt of 12 feet. Lamely rolled in a three-foot par putt to win.
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"