A police siren on the 15th tee and a low-flying helicopter that forced him to step away from his next shot still couldn’t slow down Kevin Na.

The defending champion was right at home for the second year in a row as he blistered a powerless Waialae Country Club for a career-low-tying 9-under 61 and sole possession of the first-round lead at the Sony Open in Hawaii on Thursday.

Outside of a brief run-in with the wind, and other outdoor elements, Na was dialed in from the start.

With fans allowed back on the course after it was closed to the public due to the COVID-19 pandemic last year, Na showed them what they missed.

He received a nice cheer on the ninth hole after making a short putt for eagle to go out in 29, and then moved past Jim Furyk, who led the morning groups with an 8-under 62, getting up-and-down on 18 for his seventh birdie of the day. He did not have a bogey.

“I played unbelievably well. I did everything well today and my iron play was amazing,” said Na, who gained more than six strokes tee to green, best in the field. “I tell you what, I had a chance for a 59. I gave it all I could. I’m a little disappointed my putts didn’t fall. Some of the good putts that I hit didn’t fall, but it’s still a good round.”

A 7-footer gave Na his sixth birdie of the round on 12 to get him to 8 under and make the course record of 59, shot by Justin Thomas in 2017, a possibility.

Na missed a putt inside of 10 feet for birdie on 14, a rarity on Thursday, and then had a good look for birdie on 15 from 12 feet despite distractions on each of his first two shots on the hole.

A police siren briefly paused his routine before his drive, and then he had to step away from his approach shot as a helicopter flew over. He still stuck it for a good look for birdie on one of his 15 greens hit in regulation.

“I feel like if there’s some distraction, I’ll back off, and you should, but you know, what I felt like (out there) was I was in the zone and I was pretty focused,” Na said.

Officials had a little over a week to get the course in shape after heavy rains pounded Oahu during the holiday season and left hole No. 10 under water early last week.

The rough was a bit higher than normal, but the soft greens allowed for low scoring without much wind to deal with.

Out of the 144 players who teed it up in the PGA Tour’s first full-field event of 2022, 99 finished under par.

“I remember this golf course being a lot more brown, a lot more bounce, a lot more roll,” said Furyk, who won the 1996 United Airlines Hawaiian Open. “The golf course is a lot greener. I remember heavy rough and we got some heavy rough this year … but guys can be more aggressive with the iron shots.”

A 17-time winner on the PGA Tour, Furyk played holes 14-17 in 5 under after his hole-in-one from 186 yards on the par-3 17th for his sixth ace on tour, tying him for third-most since the tour began tracking hole-by-hole scores in 1983, according to the PGA record book.

He’s had so many he couldn’t come up with the last time he made one in a Tour event.

“I have to think about it. I don’t know when the last one in competition was, but I made some at Colonial, Memorial, Pebble Beach, AT&T,” Furyk said as he kept thinking back. “I made one at Monterey Peninsula, U.S. Open at Winged Foot. That was a practice round. Made a bunch in tournaments, but the last one, I’m not sure.”

For the record, the last one came at the Bridgestone Invitational in 2011, where he’s aced a hole twice in his career.

Since then, Furyk has won once more on the PGA Tour. After turning 50, he began playing on the Champions Tour in 2020, winning three times.

Although he’s not playing full time on the PGA Tour these days, the competitive drive is still there, evidenced by his mastery of the Waialae greens.

Furyk holed more than 156 feet of putts and led the field in strokes gained putting, even without needing one on 17.

“I led the day off with a three-putt and from there just putted beautifully,” Furyk said. “Just kind of got on a roll. Left a couple of them short, actually, on the second side. But everything was kind of at the hole and on target, and giving some putts a chance to go in.

“I want to be competitive. I want to compete and put myself in position in the hunt and also want to get a feel for where my fame is and set up what I wanted to work on for the year.”

Russell Henley, who won the Sony as a rookie in 2013, played his way into a second-place tie with Furyk with birdies on 14 and 15 before closing with three consecutive pars late in the day.

“I hit a lot of fairways, and from there I could attack,” Henley said. “It’s a sweet place, just beautiful, and a fun course to play, and I have a lot of great memories from coming back every year.

Patton Kizzire, the 2018 champion, is one of five golfers tied for fourth at 7 under.

Matt Kuchar, the 2019 champion, and Ryan Palmer, who won here in 2010, both shot 6-under 64, putting six prior champions all within three shots of each other after the first round.

Defending champion Cameron Smith, who won on Maui last weekend, had birdies on two of his final three holes to shoot 67.

Joshua Creel, who shot 2-over 72 in the morning, was forced to withdraw after his round after testing positive for COVID-19.