Shane Lowry leads Arnold Palmer Invitational after hot back nine

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.

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.

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.

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.