The British Open playoff format consists of a four-hole aggregate match to decide its winner, and the four holes played differ depending on the golf course.
This year for Carnoustie, if two or more players are still tied, they’ll play holes 15, 16, 17 and 18. The 16th is a par 3, and the other three are par 4s. It’s no easy test, as the closing trio features three of four hardest holes this week. The 15th is ranked as the eighth-hardest hole.
The British Open first used the four-hole aggregate system in 1989, when Mark Calcavecchia beat Wayne Grady and Greg Norman.
It’s been used nine times in the Open’s history, most recently at St. Andrews in 2015, when Zach Johnson (15) out-lasted Louie Oosthuizen (16) and Marc Leishman (18).
As for the other playoffs in majors, the Masters uses a sudden-death playoff, the PGA Championship has a three-hole aggregate playoff and the U.S. Open has a two-hole aggregate playoff.