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.
Lowry started for Leeds in the Football League Trophy Northern Area Final, second leg game against Carlisle United, in which the game was lost with Lowry missing the decisive penalty in sudden death in the penalty shootout. After the game it appeared as though Lowry was attacked by a set of Carlisle supporters who had invaded the pitch. After starting every game for Leeds Lowry was dropped from the Leeds squad for the match against Brentford after suffering an injury, before returning to Villa when his loan spell ended. On 25 March 2010 Lowry re-signed for Leeds for a second loan spell, with his loan lasting until the end of the season. Lowry started at left back for Leeds against Norwich City on his return to the club, a match Leeds went on to lose 1–0 in injury time. Lowry didn't overley impress the Leeds fans in his loan spell at Leeds, with him being mostly played out of position at Left back for the entire spell, he was substituted for Jonathan Howson in the final game of the season against Bristol Rovers with 1–0 down at the time, but his loan spell ended on a high as Leeds were promoted in 2nd place after scoring two goals to go on and beat Bristol Rovers and secure promotion to The Championship.
Waste Management Phoenix Open: Two weeks after the win in Abu Dhabi, made his eighth consecutive start in the Waste Management Phoenix Open, where he found himself three strokes off the lead after 54 holes. A final-round 4-under 67, capped off by a clutch birdie on the 72nd hole, forced sudden death with Hideki Matsuyama. On the fourth extra hole, the par-4 17th, an errant tee shot found the water hazard for the second time of the day. Matsuyama made par to win. Ranked second in Strokes Gained: Tee To Green and T1 in Strokes Gained: Total at TPC Scottsdale.
Frys.com Open: At the Frys.com Open in Scottsdale, Ariz., reached a three-way playoff with Jamie Lovemark and eventual-winner Troy Matteson. Began the final round four strokes behind Matteson, but played his first five holes in 5-under, punctuated by a hole-in-one from 211 yards at the par-3 fifth hole. After finishing T2 in the playoff, he had recorded all eight of his professional rounds in the 60s. Thanks to the T7 in Las Vegas at the Justin Timberlake Shriners Hospitals for Children Open and T2 finish at Grayhawk GC, he surpassed No. 150 from the 2008 money list, earning special temporary membership on TOUR for the remainder of the season.
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.
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.