Former favourite Rory McIlroy has slipped to ninth in the pecking order.
American Brooks Koepka is the clear favourite to win the Masters, following a blistering opening round at Augusta National.
The former world number one has been cut from 28/1 into 5/1 to win the major and is comfortably the most backed golfer in the last 12 hours.
Since play commenced yesterday, 16% of all bets on the eventual winner have been placed on Koepka donning the Green Jacket come Sunday.
Elsewhere, Dustin Johnson sits second favourite at 13/2, followed by Bryson DeChambeau (7/1), Jon Rahm (12/1) and Phil Mickelson (14/1).
Tiger Woods is also 14/1 to win yet another Green Jacket, with Rickie Fowler (16/1), Adam Scott (25/1) and Rory McIlroy (25/1) just outside of the chasing pack.
Oddschecker spokesperson George Elek: “Koepka is the early standout and has put himself in a great position. That's translated into what the public is punting, with Koepka easily the most popular.
"But, with the likes of Dustin Johnson breathing down his neck, he’ll know that there is a long way to go before thinking about a fourth major."
