Walking down the 18th fairway in the opening round of the Korn Ferry Tour's Astara Golf Championship in Bogota, Colombia, on Thursday, Cristobal Del Solar wasn't sure of his score.

"What are we at?" Del Solar asked his caddie.

"I don't know, look at the scorecard," the caddie replied.

The 30-year-old from Chile ended up posting the lowest-ever score in a PGA Tour-sanctioned event with a 13-under 57. He made a two-putt par on the 18th hole, narrowly missing a 6-footer that would have given him a 56.

Del Solar carded nine birdies and two eagles during a bogey-free round. He opened with a front-nine 27 and had a 30 on the back.

Del Solar's round also tied for the lowest ever in a professional tournament; Ireland's David Carey posted an 11-under 57 on a par-68 course on the Alps Tour in 2019.

The conditions at the Pacos Course at Country Club de Bogota were ripe for a low score. The course is 6,254 yards and plays even shorter, as Bogota sits about 8,600 feet above sea level. Rain earlier in the week softened its greens. Players were allowed to lift, clean and place their balls under preferred lie rules because of soggy conditions.

"It was a very short course, I mean really short," Del Solar said in a video conference from Colombia. "[There were] a lot of holes that were drivable; I wouldn't say drivable, but within 20 yards of the green. I wouldn't necessarily get on the green, but I was around it. The course was definitely set up to shoot a low score.

"Now, when you go onto a course like this, you don't think, 'I'm going to shoot 57.' You just go out there and do your best and hope it's a really low score. You've still got to do it, obviously."

Germany's Stephan Jaeger held the previous KFT record of 12-under 58 at the 2016 Ellie Mae Classic at TPC Stonebrae in Hayward, California.

Jim Furyk recorded a 12-under 58 in the final round of the 2016 Travelers Championship at TPC River Highlands in Cromwell, Connecticut, the lowest score in PGA Tour history.

Bryson DeChambeau made four straight birdies to post a 12-under 58 at a LIV Golf League tournament at the Greenbrier in White Sulphur Springs, West Virginia, on Aug. 6.

Del Solar had a 4-stroke lead after his record-breaking round. He didn't plan to do much celebrating with 54 holes still to play in the tournament.

"Today's the first day of the tournament," he said. "I've to play again tomorrow. Hopefully by Sunday, I'll have also amazing news. Hopefully, I'll celebrate Sunday as well."

The former Florida State golfer turned pro in 2017 and won four times on the PGA Tour Latinoamerica circuit, including twice in 2022. He was a Korn Ferry Tour rookie last season and is 14th in points this season. He is ranked 259th in the world.

"I played really good last year and had really good finishes," Del Solar said. "It wasn't quite enough to get on the PGA Tour. That's where I want to be; that's one of my dreams. I think overall my consistency has improved the past couple of years. My technique has improved, and I've gotten stronger mentally."