Mackenzie Hughes leads after the opening round of the Travelers Championship at TPC River Highlands, but Rory McIlroy is just three shots behind as he looks for his first win of the year.
Hughes put together a sensational opening round of 60, with 10 birdies and not a single birdie in what was another low scoring day on the PGA Tour.
The Canadian, ranked 158th in the World Ranking, got off to a perfect start, rolling in a 30ft putt at the 11th (his second hole) for birdie, before making five more in a row from the 14th to reach the turn in 29.
Hughes found more birdies on his back nine and needed to drain a long-range putt at his final hole to shoot a famous '59 round,' but the 29-year-old left it short and tapped it in for par.
"I was really trying to make sure I just gave it [putt on his final hole] a chance and roll it past the hole and I don't know, just didn't hit it," Hughes said. "Still super-excited about shooting 60 and it's a round that I'll remember for a long time."
McIlroy looked in much better form than of late and was on fire off the tee using his TaylorMade SIM driver and SIM Max 3-wood.
The Northern Irishman, who was grouped with Phil Mickelson and Bryson DeChambeau, eagled his fourth hole (13) before making back-to-back birdies, but dropped his only shot of the day at the par-3 16th, his seventh hole.
The World No.1 made four more birdies on his back nine to post a 7-under score of 63, leaving him just three shots behind Hughes heading into Friday's round.
Xander Schauffele and Viktor Hovland share a tie for 2nd with McIlroy, whilst Phil Mickelson and Sergio Garcia are part of a four-man pack in T5 at 6-under par.
DeChambeau continued his fine form with a 5-under par opening round and Jon Rahm will be looking to make a move on Friday after his 4-under par round on Thursday.