The world’s top ranking and the PGA Championship are in Jordan Spieth’s sights as the upstart American enters the year’s final major as a 6/1 favorite. Already claiming the year’s first two slams and coming one stroke away from a playoff at the British Open last month, the 22-year-old Spieth is well ahead of a field of seasoned veterans before Thursday’s first round at Whistling Straits in Kohler, Wisconsin.

Spieth sits above Australia’s Jason Day and defending PGA champ and hobbled No. 1 Rory McIlroy, who are both listed at 12/1 in odds released by Bubba Watson and Dustin Johnson are next up at 15/1, followed by Justin Rose and Rickie Fowler at 22/1.

The big money is presently on Spieth, the only player whose odds are in the single-digits, with most bets at the SuperBook and William Hill’s Nevada sportsbook on him to win, according to ESPN.

Spieth is attempting to be the first golfer since Tiger Woods to win three majors in one year, less than a month removed from his tie for fourth place at St. Andrew’s. He would lead the entire field with 24 birdies during the tournament, highlighted by his 6-under third-round performance, but ultimately missed out on the championship playoff.

Sporting five victories and 14 top 10 finishes over 21 events this season, Spieth stands to usurp McIlroy’s crown by coming in at least third should a number of factors falling in his favor.

McIlroy’s return from a serious ankle injury he suffered before the British Open has certainly given Spieth the edge heading into the final major. The Northern Ireland native and two-time PGA victor ruptured a ligament in his left ankle, and was forced to pull out of the British, but announced he will make his official return at the PGAs.

Yet McIlroy isn’t Spieth’s only competition as there are a number of former champions among the field. Keegan Bradley is an 85/1 longshot, but he pulled off a PGA win back in 2011, while 30-year-old German Martin Kaymer is listed at 55/1 and he won when the tournament was last held at Whistling Straits in 2010.

Woods is a four-time PGA champion, last taking the throne in 2007 with a final score of 8-under, but his poor play and injury history over the last couple of years slots him at 44/1. Two-time champ Vijay Singh is way back at 375/1, while 2002 winner Rich Beem is one of three biggest longshots listed at 2000/1.

Check out the early odds leaders below.

Odds to Win PGA Championship

Jordan Spieth 6/1

Jason Day 12/1

Rory McIlroy 12/1

Bubba Watson 15/1

Dustin Johnson 15/1

Justin Rose 22/1

Rickie Fowler 22/1

Adam Scott 25/1

Henrik Stenson 25/1

Brooks Koepka 40/1

Louis Oosthuizen 40/1

Phil Mickelson 40/1

Tiger Woods 40/1

Hideki Matsuyama 45/1

Sergio Garcia 45/1

Jim Furyk 50/1

Shane Lowry 50/1

The full list can be found at here.