(Reuters) - Top seed Rory McIlroy has been grouped with three highly-rated Americans for this week's WGC-Cadillac Match Play Championship in San Francisco.
A draw on Monday put Northern Ireland's world number one up against reigning FedExCup champion Billy Horschel, seven-times PGA Tour winner Brandt Snedeker and major champion Jason Dufner in round-robin play starting on Wednesday at TPC Harding Park.
The Match Play Championship, the first of the season's elite four World Golf Championships (WGC) events, was a knockout event from its inception in 1999 until last year, which meant that many of the big names were sent packing on the first day.
Therefore, the format was tweaked this year in an effort to give top seeds a chance to overcome one bad match.
Masters champion Jordan Spieth, the second seed in the field of 64, drew Englishman Lee Westwood, American Matt Every and Finn Mikko Ilonen.
Spanish 10th seed Sergio Garcia was drawn in an all-European group with Jamie Donaldson, Bernd Wiesberger and Tommy Fleetwood.
"It's an all-European group so it will be pretty friendly I think but no easy matches," Donaldson told Golf Channel.
Defending champion Jason Day of Australia is grouped with American Zach Johnson, South African Branden Grace and American Charley Hoffman.
The top player in each of the 16 four-man groups was awarded to players based on their position in the world rankings while the rest of the group was filled through a random draw.
Each golfer will play the other three men in his group in 18-hole match play over the first three days. The top player from each group will then advance to the final 16, when the event will become sudden death.
Two big names already missing are Tiger Woods and Phil Mickelson. Woods did not qualify, while Mickelson has withdrawn for personal reasons.