Oddsmakers have Jon Rahm, fresh off his first win at a major, as the clear-cut favorite at the 149th Open this week at Royal St. George's.
Rahm is the favorite at 7-1 at Caesars Sportsbook by William Hill. No other golfer has single-digit odds.
Rahm has been in top form since early June. He had a commanding 6-shot lead heading into the final round at the Memorial Tournament, before being forced to withdraw after testing positive for COVID-19. Upon returning from quarantine, he won the U.S. Open, his first major, and finished seventh last week at the Scottish Open.
The betting action on The Open at U.S. sportsbooks is relatively evenly divided, with Rahm and Koepka receiving the most support. More money has been wagered on Rahm than any other golfer at Caesars Sportsbook at William Hill, while Koepka has attracted the most support at PointsBet and BetMGM.
"The two guys that I'm most concerned about right now are [Victor] Hovland and [Louis] Oosthuizen," Nick Bogdanovich, director of trading for William Hill U.S., said in a company release Monday. "Both are playing really well, and we've got good liability on them."
Oosthuizen is 30-1, and Hovland is 40-1.
Weather forecasts at Royal St. George's in Sandwich, England, call for temperatures in the low 70s, with winds around 10-15 mph for the early rounds and calming for Sunday.
Darren Clarke won the last Open at Royal St. George's in 2011. He was one of only four players who finished under par. Clarke is 500-1 this week.
Shane Lowry, who won the 2019 Open, is 33-1. The 2020 Open was canceled because of the coronavirus pandemic.