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Since winning the PGA Championship in 2016, Jimmy Walker has struggled to shake off the effects of Lyme Disease. He registered just one top 10 in 2017 and dropped to 68th in the world, down from 21st. Can he recover his game as he recovers his health?
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The former NCAA individual champion won on the Web.com Tour in 2017 at the Air Capital Classic. The PGA Tour rookie has made three of five cuts this season, with his best finish a tie for 13th.
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Hall in 2017 won the Ladies' European Tour Order of Merit, registered two major top-10s, and went 2-3-0 in her maiden Solheim Cup appearance. The 21-year-old made it through Qualifying School and will play her rookie season on the LPGA in 2018.
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The 18-year-old made her Solheim Cup debut and wowed crowds with her length of the tee, going 1-1-1. After celebrating her 19th birthday, she capped her year with a win at the Omega Dubai Ladies Classic.
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Hossler first made himself known to golf fans when he took the lead at the 2012 U.S. Open as a 17-year-old. Now a Web.com graduate, Hossler registered a pair of top-10 finishes this fall at the Shriners and Sanderson Farms.
6 / 15
Brittany Altomare came out of nowhere and very nearly captured her first major victory at the Evian, losing to Anna Nordqvist in a playoff. Was that performance a one-off, or a sign of what is to come?
7 / 15
Bud Cauley racked up five top-10 finishes last season and added two more this fall. Is this the year the former Alabama standout finally breaks through?
8 / 15
Ian Poulter looked as if had lost his PGA Tour card last year before Brian Gay spotted an error in the way Poulter's FedExCup points were being tabulated as part of his medical extension. With a second lease on life, Poulter finished T-2 at The Players and third at the Canadian Open. He's now 54th in the world, once again knocking on the door of the game's biggest events.
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The 19-year-old is a three-time Ladies European Tour winner who represented India in the Rio Olympics in 2016. She recorded just one top-10 in her LPGA rookie season in 2017 but may be primed for bigger things in 2018 after a year of seasoning.
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Chesson Hadley won twice on the the Web.com Tour in 2017, topping the regular season and finals money lists and taking home the circuit's player of the year award.
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The former top-ranked amateur in the world finished 60th in FedExCup points in his rookie season and was runner-up to Henrik Stenson at the regular-season finale, the Wydnham Championship.
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Nelly Korda racked up five top-10 finishes in 2017 and finished 20th in the Race to the CME Globe. She's only 19, and she's not just Jessica's younger sister.
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The 2010 U.S. Amateur champion has spent much of his professional career on the European Tour but now has full status on the PGA Tour after winning a Web.com Finals event. He's now 52nd in the world, close to major and World Golf Championships invites.
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Jin-Young Ko is a 22-year-old, 10-time KLPGA winner who claimed LPGA status with her win at the KEB-Hana Bank Championship in October. She is already 18th in the world and about to be an LPGA rookie.
15 / 15
Like Poulter and Uihlein, Dylan Frittelli is so close to cracking the OWGR top 50, at No. 53. He won twice on the European Tour in 2017 and nearly picked up a third title in China, where he lost in a playoff.