Los Angeles - Michael Kim made his long-awaited first US PGA Tour triumph a record-breaker Sunday, winning the John Deere Classic by eight strokes with a final-round 66. 

The South Korean-born American finished with a 27-under total of 257 - one stroke better than the previous tournament record set by Steve Stricker in 2010.

Kim also posted the tournament's largest margin of victory - by four strokes - since it moved to TPC Deere Run in 2000. 

"I'm just really thankful and proud," said Kim. "I feel like I've been running on fumes the entire back nine. I'm just super-thankful, thankful to my parents, my team, my coaches ..." 

A day after celebrating his 25th birthday, Kim punched his ticket to next week's Open Championship at Carnoustie. 

Italy's Francesco Molinari and Americans Joel Dahmen, Sam Ryder and Bronson Burgoon shared second on 265. 

Kim took a five-shot lead over Burgoon into the final round and wasted no time in stretching his lead. 

He opened with three straight birdies at the Silvis, Illinois, layout, rolling in a 24-footer at the third. 

Kim stuck his second shot two feet from the pin for a birdie at the eighth, and drained a 21-footer for birdie at 16 to reach 27-under. 

He two-putted for par from about 80 feet at the last, holing a five-footer to complete a bogey-free final round and getting an emotional hug from his parents, who to his surprise had just flown in on Sunday. 

Kim, a contemporary of young tour standouts Jordan Spieth and Justin Thomas, enjoyed an outstanding amateur career. 

But he didn't get his first PGA victory until his 84th start - a win that certainly wasn't looking likely when he missed the cut in five of six prior starts. 

"It's been a tough first half of the year, but to be able to finish out in style like this means a lot," said Kim, who added he had felt his game coming around. 

"Even in the last couple of weeks I felt like my game was getting there, getting there. I just felt like I needed a couple of good starts of the rounds, couple of good swings. I just got off to a great start on Thursday and kept it going on Sunday." 

Kim, one shot off the lead after his first-round 63 on Thursday, moved atop the leaderboard during the weather-disrupted second round and extended his lead in a third round plagued by two more weather delays. 

Molinari, a runaway winner at the Quicken Loans National two weeks ago, fired a final-round 64 to seize his share of second. Dahmen posted a 65 and Ryder a 66. 

Burgoon, playing in the last group with Kim, was unable to mount a charge, finishing with three birdies and a bogey in his two-under 69 but making a solid up-and-down for par from a greenside bunker at the last to maintain his share of second.

Leading final-round scores on Sunday in the US PGA Tour John Deere Classic in Silvis, Illinois (USA unless noted, par-71):

257 - Michael Kim 63-64-64-66

265 - Francesco Molinari (ITA) 65-66-70-64, Joel Dahmen 64-71-65-65, Sam Ryder 66-66-67-66, Bronson Burgoon 68-62-66-69

266 - Harold Varner 67-65-66-68

268 - Kevin Streelman 66-71-66-65, John Huh 70-63-69-66, Chad Campbell 66-70-66-66, Keith Mitchell 67-68-66-67, Andres Romero (ARG) 64-71-64-69

269 - Scott Brown 65-72-65-67, Steve Wheatcroft 62-68-71-68, Tyler Duncan 66-72-63-68, Matt Jones (AUS) 68-63-66-72

270 - Zach Johnson 69-70-67-64, Mackenzie Hughes (CAN) 72-65-68-65, Kim Whee (KOR) 65-68-70-67, Parker McLachlin 66-66-70-68, Seamus Power (IRL) 68-68-65-69, David Hearn (CAN) 66-64-70-70, Johnson Wagner 64-66-70-70

271 - Dominic Bozzelli 70-65-71-65, Joaquin Niemann (CHI) 69-69-68-65, John Merrick 66-70-70-65, Chris Kirk 66-72-66-67, Richy Werenski 68-69-67-67, Derek Fathauer 68-67-68-68, Fabian Gomez (ARG) 66-70-67-68