Jeff Knox of Augusta, Ga., shot an opening round 4-under 66 to set the early pace at the 2025 Jones Cup Senior Invitational at Sea Island Golf Club, the Seaside Course, in St. Simons Island, Ga. 

The Augusta native recorded five birdies and one bogey in the round and birdied the opening two holes of the tournament.

Kevin Vandenberg of Pulaski, N.Y., and Steve Harwell of Mooresville, NC., are both T2 after rounds of 3-under 67 and are one shot back of Knox heading into the second round.

Vandenberg, the No. 1 ranked player in the AmateurGolf.com Senior Rankings, was the 2024 AGC Senior Player of the Year and is off to a hot start this year as well, securing wins at the 2025 Golfweek Senior POY Classic and 2025 Plantation Senior.

2020 and 2023 Jones Cup Senior champion Bob Royak of Alpharetta, Ga., Billy Mitchell of Dunwoody, Ga., Jon Lindstrom of Denver, Colo., Dave Bunker of Canada, and Michael Hughett of Owasso, Okla., are all T4 at 2-under. 

19 golfers are within four shots of the lead.

Knox is a member of the Georgia Golf Hall of Fame. His role as a marker at the Masters began in 2003. Over that time, he has been paired with Rory McIlroy, Bubba Watson, Ernie Els, Craig Stadler, Jim Furyk, Sergio Garcia, Miguel Angel Jimenez, and Steve Stricker, amongst others.

“He’s the best I’ve ever seen on Augusta’s greens,” McIlroy said after his round with Knox in 2014. Justin Thomas has echoed that sentiment. 

Knox also holds the unofficial Augusta National course record at 11-under 61.