Irish duo Graeme McDowell and Shane Lowry started well at the Workday Charity Open in Ohio to sit three and four shots respectively off leader Colin Morikawa after the opening round.
A round of 65 saw American Morikawa set the pace and take the clubhouse lead on -7 in benign conditions at Muirfield Village Gold Club.
The 23-year-old, making his debut at the Muirfield Village Golf Club, would have enjoyed a two-stroke lead but his putt on 18 came up agonizingly short and he was forced to settle for his lone bogey of the day.
But he wasn't discouraged by how his round ended.
"It happens, I think it was just slight fatigue," he said.
"If I look at the entire day it was very consistent and I can take a lot of positives heading into tomorrow."
Morikawa is a stroke clear of Canadian Adam Hadwin, who began his round with a bogey at the par-four 10th but was flawless the rest of the way as he shot a six-under 66.
"It's been building for a while," said Hadwin, who finished in a share of fourth place last week in Detroit.
"Obviously, had a good week last week and kind of took that momentum into the round."
McDowell is in a share of seventh place on four under par following a round of 68, but it could have been even better for the 2010 US Open winner who will be frustrated by handing back three shots at the turn.
A bogey on the 18th hole (his ninth) and double bogey on the second (his eleventh) undid the Portrush native's good work early on.
However, McDowell made the most of the good weather on the home straight to add four more birdies - seven in total - to shoot up the leaderboard.
Lowry enjoyed a similar round with bogeys on the fourth, 14th and 17th, offset by four birdies and an impressive eagle on the par-five seventh.
The Offaly man is a shot further back from McDowell on three under and in a tie for 18th.
Canadian Nick Taylor, Japan's Hideki Matsuyama and Americans Zach Johnson and Aaron Wise lurk two back after rounds of 67.
World number five Brooks Koepka, who has not competed since his caddie tested positive for Covid-19 two weeks ago, struggled on the front nine and ultimately had to settle for a two-over 74 at the Jack Nicklaus-designed layout.
Three-times major winner Jordan Spieth battled back from a rough start to finish at even par while Phil Mickelson's solid start was undone by a disastrous back nine where he had four bogeys and a double for a one-over 73.
This week's event is being played at Ohio's Muirfield Village in place of the John Deere Classic, which was supposed to be held in Illinois but was cancelled due to state-related challenges regarding the Covid-19 pandemic.