Webb Simpson had to settle for a share of the course record at Sawgrass as the famous 17th hole claimed another victim in the Players Championship.
An eagle and nine birdies, including six in a row from the 11th, left Simpson needing to birdie the final two holes to join the elite group of players to break the magical 60 barrier on the PGA Tour.
— PGA TOUR (@PGATOUR) May 11, 2018
However, the former US Open champion then double-bogeyed the 17th after his tee shot hit the wooden sleepers which form the edge of the green, bounced on to the putting surface and into the water.
And a par at the last meant Simpson had to be satisfied with becoming the seventh player to shoot 63 in the tournament's history, the 32-year-old's 15 under par total also equalling the 36-hole scoring record.
"I got off to a great start with an eagle on two and it was a day where on the greens everything looked good to me and I felt I was going to make putts maybe I don't normally make," Simpson told Sky Sports.
"Seventeen was a bummer but it's a tough hole. I blocked it a little bit and probably should have hit one more club, but other than that a great confidence builder for me.
"The challenge is to treat tomorrow just how I treated today, one shot at a time and try to attack when it's the right opportunity. You still have to play defensive around here whether you're five back or five ahead."
Simpson still enjoyed a tournament record five-shot lead over former Masters champion Charl Schwartzel, American Patrick Cantlay and New Zealand's Danny Lee, while Tiger Woods made the halfway cut on the mark of one under par as Rory McIlroy made an early exit following a 74.
"I was just a touch off today," Woods told reporters after his 71. "I didn't make many birdies. I had my chances. I didn't hit it close enough. The course could have been had today. It's so hot, it's playing short, the greens are receptive."
Schwartzel, who had earlier added a bogey-free 66 to his opening 68, has 11 European Tour titles to his name but has won just once on the PGA Tour - the 2016 Valspar Championship - since his victory at Augusta in 2010.
But the 33-year-old has been coming into form with a third place alongside Louis Oosthuizen in the Zurich Classic of New Orleans followed by a top-10 finish at Quail Hollow on Sunday.
"I've been making a bunch of birdies in the last few weeks and making just as many bogeys and the difference this week is obviously making a lot less bogeys," Schwartzel, who has dropped just one shot in 36 holes, said.
"It started changing for me on the back nine on Friday at New Orleans. I started playing a lot better and have rolled with it. All the swing work that I've done for the last couple of months I'm feeling comfortable with it now and it's paying off."
Schwartzel has never finished inside the top 25 at Sawgrass - "I've even missed this tournament a few times, willingly!" he joked - but a new approach is paying dividends.
"It's the first time I've not come here from South Africa," he added on Sky Sports. "I normally go back to South Africa after Augusta and then fly from there and start with this tournament.
"I've played my way into it and it's obviously the way to go. This is a hard tournament to come to after a three-week break."