Irishman Shane Lowry rolled in a birdie at the par-3 17th hole to take a one-stroke lead after one round of the Arnold Palmer Invitational on Thursday in Orlando, Fla.

In the field for the fourth signature event of the season on a sponsor's exemption, Lowry carded a 6-under 66 to move a shot in front of Justin Lower and Japan's Hideki Matsuyama.

It's not a position Lowry is used to in this tournament, and he didn't mince words about his record.

"It's horrific," said Lowry, adding that he had "no idea" why he played so well Thursday. "I played here six times, I missed the cut five times. Last year, I made the cut and shot 81 on Saturday and finished (67th at 5 over). Going out there with very low expectations today. I knew I was playing well. Golf's a funny game. Just had it under control today."

Lowry played the front nine at Bay Hill Club & Lodge in 1-under 35 before making his push. He started the back nine birdie-birdie-eagle-birdie -- chipping in from 18 feet for eagle at the par-5 12th -- before a bogey halted his run at the par-3 14th.

"It's funny, when you're out there playing and you get on a run like that, it does feel pretty easy," Lowry said. "Then you start -- I spoke about this with my coach this week -- I said, 'This is the type of place where you get on a run and it feels easy, but then you get on a run the other way and start making bogeys, it feels like you're never going to make a par out here again.' It's one of them courses, it's very difficult."

His luck turned at the last par 3, though, as his tee shot at No. 17 landed fewer than 8 feet from the pin to set up the go-ahead birdie.

Lower's round featured seven birdies at Nos. 5, 6, 10, 11, 15, 16 and 18, and bogeys at Nos. 3 and 14.

"I putted well, which is nice. I hit some shots really close, which is always nice," said Lower, who joined the tour in 2022 and is seeking his first victory after playing 71 events. "Kind of hard to do around here, but the greens were a little more receptive than I thought they would be. Hopefully, they don't go and change that overnight. No, just an overall solid day."

Matsuyama also carded two bogeys, at Nos. 11 and 15. But he more than made up for it with an eagle at the par-5 No. 16 and birdies at Nos. 1, 4, 5, 10 and 12.

Russell Henley, Lee Hodges, Sam Burns and Sahith Theegala are tied for fourth at 4-under 68. A large group at 3-under 69 includes notables Justin Thomas, Jordan Spieth, Brian Harman, Will Zalatoris and Canadian Nick Taylor. World No. 1 Scottie Scheffler is at 2-under 70, as are Collin Morikawa and Australia's Jason Day.

Though the Arnold Palmer Invitational is a signature event with a $20 million purse, as a player-hosted invitational it features a 36-hole cut down to the top 50 players and ties. That's bad news for Northern Ireland's Rory McIlroy and Englishman Tommy Fleetwood, who are among the group tied for 49th at 1-over 73.

Patrick Cantlay (74), Matt Fitzpatrick of England (74) and Rickie Fowler (75) also had rough starts. Defending champion Kurt Kitayama opened with a 6-over 78, second-to-last in the 69-player field.

--Field Level Media