AUGUSTA, Georgia :Scottie Scheffler will launch his Masters title defence on Thursday alongside Justin Thomas and Spanish amateur Jose Luis Ballester while Rory McIlroy, looking to complete the career Grand Slam, will go out in one of the final groups. World number one Scheffler, bidding to become only the fourth player to repeat as Masters champion, will go out in the 14th group at 10:15 a.m. ET (1415 GMT), one group behind three-times champion Phil Mickelson, Jason Day and Keegan Bradley. Northern Ireland's McIlroy, who with a win would become the sixth player to complete the career Grand Slam of golf's four majors, will tee off in the fourth-to-last group at 1:12 p.m. ET alongside 2024 runner-up Ludvig Aberg and Akshay Bhatia. Playing one group behind will be a high-profile threesome of major champions that consists of Japan's Hideki Matsuyama, LIV Golf's Bryson DeChambeau and Ireland's Shane Lowry. Former Masters champion Jon Rahm, one of 12 players from the Saudi-backed LIV Golf circuit in the field at Augusta National this week, will head out in the day's penultimate group with Wyndham Clark and England's Tommy Fleetwood. World number three Xander Schauffele, seeking his third victory in four majors this week, will follow McIlroy's group around the course in the company of Australia's Adam Scott and Norwegian Viktor Hovland. Masters debutant Davis Riley will hit the first competitive shot of the week when he sets out at 7:40 a.m. ET alongside Patton Kizzire after honorary starters Gary Player, Jack Nicklaus and Tom Watson hit shots off the first tee. The forecast for Thursday is for a low of 48 degrees Fahrenheit (8.9 degrees Celsius) and a high of 76 F with a 60 per cent chance of showers and isolated thunderstorms during the night.