Miami - Kyle Stanley, looking for his first PGA Tour title since 2017, fired an eight-under par 64 on Thursday to take a two-shot first-round lead in the Puerto Rico Open.
Stanley posted a career-high nine birdies, hitting all 18 greens in regulation and dropping his only shot of the day at the eighth.
He birdied the first three holes - and four of the first five - on the par-72 Coco Beach Golf and Country Club course.
He added another four birdies in a row from the ninth through the 12th and picked up one last birdie at 15.
"Just kind of caught a hot putter," Stanley said. "Ball-striking was pretty good and felt like I drove it well, too. Just a pretty solid round of golf."
Pretty windy out there, so I'm really happy with the round."
It was a welcome turnaround for Stanley, winner of the 2012 Phoenix Open and 2017 Quicken Loans National who has made just four cuts in 11 starts so far in the 2019-2020 season.
"To be honest, I really haven't been playing that well the past month or so," Stanley said. "I really struggled with my ball-striking last week in LA, but felt like I putted pretty well. Just tried to clean up a few things in my swing and continue with some good putting prep leading into today."
A victory in Puerto Rico - a tournament played opposite the elite World Golf Championships Mexico Championship - would see him secure his US PGA Tour card for another two seasons.
Half a dozen players shared second on 66: Argentina's Emiliano Grillo, Sweden's Henrik Norlander, Australian Rhein Gibson and Americans Josh Teater and Peter Uihlein.
Leading first-round scores on Thursday in the PGA Tour Puerto Rico
Open in Rio Grande, Puerto Rico (USA unless noted, par-72):
64 - Kyle Stanley
66 - Peter Uihlein, Josh Teater, Emiliano Grillo (ARG), Chris Couch, Henrik Norlander (SWE), Rhein Gibson (AUS)
67 - Martin Laird (SCO), Jay McLuen, Scott Brown, MJ Daffue (RSA), Wes Roach, Julian Etulain (ARG)
68 - Robby Shelton, Ted Potter, Kiradech Aphibarnrat (THA), Viktor Hovland (DEN), Jhonattan Vegas (VEN), Mark Anderson