Leishman pulled within a shot of eventual winner Tyrrell Hatton late on the back nine on Sunday, but his fightback was only good enough for second as the Englishman secured his first PGA Tour victory.

Hatton's 74 at Orlando's Bay Hill course left him at four-under par and his 284 was the highest-ever score by a winner in the 54-year history of the Palmer event.

"It's an incredible feeling to win at such an iconic venue and with Arnie's (Palmer's) name to it," Hatton said.

RELATED: Take a look inside Hatton's bag

Leishman, who won the Palmer event in 2017, came from four shots back with nine holes to play but his 73 left him runner-up at three under (285).

Korea's Sungjae Im (73) was third at two under.

Hatton's win comes with a three-year exemption on the PGA Tour and a US$1.7 million winner's cheque, while moving him 10 places up the world rankings to No.22.

The silver lining for Leishman, who won the US Tour event at Torrey Pines in January, is he jumps six places to World No.15.

Hatton claimed his first PGA Tour title at Bay Hill. PHOTO: Sam Greenwood/Getty Images.

"Yes, I'm disappointed, but I'm just happy that I played well," Leishman said.

"It felt like a US Open out there; fast greens, long rough, narrow fairways, and big, vocal crowds.

"Obviously, I would have liked to have won but that was a fun day and a fun week."

Leishman's hot form is timely with the elite Players Championship starting on Thursday.

He will then use the World Golf Championships-Match Play as his final hit-out before the Masters at Augusta National in April.

"This week was a really big mental test and they were all good signs," Leishman said. "Going into the Players, I feel I'm in a good place mentally and with the majors season coming up as well."

World No.1 Rory McIlroy started Sunday two shots behind Hatton but a 76 saw him share fifth place at even par.

McIlroy will reach 100 weeks in total as World No.1, the third-highest tally behind Tiger Woods (683) and Australia's Greg Norman (331).

"There have been a lot of chances (to win that I'm not) not converting, but I know the game's pretty much there," McIlroy said.

"I'll just keep knocking on the door."

Australia's Matt Jones ( 81) was 47th at nine over.

- Evin Priest, Australian Associated Press