Rafa Cabrera Bello and Kevin Na are level atop the Wyndham Championship leaderboard, two strokes clear after the opening round.
Cabrera Bello and Na carded seven-under-par 63s to set the tone at Sedgefield Country Club on Thursday.
Fresh from finishing tied for fifth at the Olympic Games in Rio last week, Spaniard Cabrera Bello continued his good form in a flawless start to his campaign in Greensboro, North Carolina.
Cabrera Bello did not drop a shot, holing five birdies and an eagle for a bogey-free round, while American Na was also blemish-free as he posted three birdies on the front nine, and picked up shots at the 10th, 11th, 13th and 15th.
Adrift of the leading pair are Derek Fathauer, Danny Lee, Luke Donald, Peter Malnati and Brandt Snedeker at five under.
Former world number one Donald was the pick of the bunch after acing the 16th hole from 159 yards.
Donald's hole-in-one meant one lucky fan had their house mortgage paid for a year courtesy of the Quicken Loans Hole-in-One Challenge, while the Englishman also won vacations for life via a special tournament promotion.
"It will make a huge deal to someone's life to have their whole year paid off," Donald said. "... I think it's going to be obviously very pleasing to someone."
A shot further back is Shawn Stefani, alongside 2013 champion Patrick Reed, Hideki Matsuyama, Jim Furyk, Johnson Wagner, Andres Gonzales, Dicky Pride, Greg Chalmers, Troy Merritt, Bill Haas, Billy Horschel, Brett Stegmaier, Sam Saunders and Andrew Landry.