Scott fired a four-under 67 to trail Englishman Tommy Fleetwood (65) by two and a group of five at five under.

But the 42-year-old Queenslander, currently world No.41, had a mixed bag carding one eagle, seven birdies, three bogies and a double bogey to be in a tie for seventh.

A little time away from the game has paid off for birthday boy Rory McIlroy.

The world's third-ranked player shot three under in his first tournament since missing the cut at the Masters.

McIlroy withdrew from the HBC Heritage following a disappointing second-round 77 at Augusta National. This controversial decision cost him a $3 million ($A4.5m) bonus for failing to meet the playing requirements for the PGA Tour's new Player Impact Program.

The Northern Irishman said earlier in the week he didn't touch his clubs for more than two weeks, adding that he needed a "reset" to gain some perspective because golf had begun to consume his life.

He looked fresh on Thursday.

"It was just really nice to be out there again," McIlroy said.

Unsurprisingly, he's off to a strong start at Quail Hollow, a course that fits his game. He has won the Wells Fargo Championship three times and finished in the top 10 nine times in 11 starts.

It was also the site of his first PGA Tour victory in 2010 and where he set a tournament scoring record at 21 under in a dominating seven-stroke win in 2015. He won again in 2021, making him the tournament's only three-time champion.

"I feel relaxed here," McIlroy added.

"I think if you come back to the site of your first win on tour, and I've gotten to know (Quail Hollow president Johnny) Harris really well and it's just a level of comfort at this golf course and at this club that I probably don't have at any other venue on tour.

"I didn't want to spend my birthday afternoon grinding on the range, so it was nice to play OK."

Fleetwood, who has won six times on the European Tour but never on the PGA Tour, finished a bogey-free round with birdies at 17 and 18.

"I just have to keep going and wait for those really big results and hopefully start contending again up at the top of the leaderboard and we'll see what we can do from there," he said.

Scott is the only Aussie under the card after 18 holes. Cameron Davis (71) is even-par, while Jason Day (72) and Harrison Endycott (74) are one and three over, respectively.

Defending champion and two-time winner Max Homa carded a one-under-par 70.