Australian ace Leishman started the final round six shots off the pace but charged into contention with a seven-under 65 that gave him the clubhouse lead at 15-under.

He trailed only overnight co-leader Maverick McNealy at that stage, before Homa grabbed the ascendancy in spectacular fashion at Silverado Resort and Spa North Course.

Leishman made eight birdies and just one bogey but ultimately felt that missed opportunities late, par-5 16th and 18th holes, cost him.

"My iron game was really good," he said.

Homa won for the second time in 2021 in California. PHOTO: Meg Oliphant/Getty Images.

"Didn't hit many fairways but drove it in the right spots to have good angles to the pins ... And obviously you have got to make the putts. The putter was pretty good today.

"A little disappointed with the last three holes ... Could have really put some pressure on but definitely happy with the week and good start to the season."

Leishman hit six of 14 fairways and 15 of 18 greens in regulation – making all putts from inside 10 feet.

It was a nice way to round out the week for the Victorian after an up-and-down few days that included two double-bogeys on Friday.

"Wherever I finish, to play golf like I have the last two days was really pleasing," Leishman said.

"Hasn't been the greatest year I would say.

"There's been patches of good stuff, third at the Travelers and top-5 at the Masters, I believe, but other than that it's been pretty lame.

RIGHT: Leishman fired the equal low round of the day on Sunday to climb the leaderboard. PHOTO: Meg Oliphant/Getty Images.

"So good to put some good scores together, get a sniff again.

"It's nice to get in the hunt, get the juices flowing. I love that, that's what we do, that's why we do it."

The 37-year-old said he will play three more tournaments over the coming weeks, twice in Las Vegas and once in Houston, before he turns his attentions to 2022.

Three strokes behind McNealy with seven holes left, Burbank native Homa holed out of the rough from 95 yards for eagle on the par-4 12th and added three birdies for his own 65 to get to 19-under – good enough for a one-stroke victory.

Homa won for the second time this year – after Riviera in Los Angeles in February – and for the third time on the PGA Tour.

McNealy shot a 68 to finish second. He birdied the 16th, then made a double bogey on 17 and an eagle on 18.

Mito Pereira (68) of Chile was third at 16-under.

Leishman was joined by Talor Gooch (68) a shot further back.

PGA Championship winner Phil Mickelson (75) faded on Sunday to be T-36 at 7 under in a group that included Australian Aaron Baddeley, whose 74 dropped him 17 places.