Thomas' round gained even greater momentum when on the 10th, he rolled a birdie putt towards the hole where it clung to the lip for 15 seconds before eventually dropping.
The only player who might have caught Thomas was Kisner who was the last player to finish the course but he three-putted from 100 feet on the 16th for a bogey and his second shot on 18 found the water to the left of the green.
Ranked ninth on the US PGA Tour for driving distance, Thomas picked up another shot on his opening nine holes to set up a back-nine charge.
Long-time leader Kevin Kisner went back to seven-under when he birdied the 15th, but three shots dropped from there saw him slip back to four-under, while Chris Stroud also struggled in the final group with a 76.
This time round, Thomas entered the final round two shots behind leader Kevin Kisner.
Thomas win at the PGA Championship is his major win on the PGA Tour.
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Prior to the Masters back in April, Baker placed a wager on Bet365 that Sergio Garcia, Rickie Fowler, Brooks Koepka, and Justin Thomas would win the Masters, British Open, U.S. Open, and PGA Championship respectively.
McIlroy last won a major in 2014, when he went back-to-back at The Open Championship and PGA Championship. He had already lifted three titles this season, including in Hawaii where he shot a 59.
He finished two strokes ahead of Francesco Molinari, Patrick Reed, and Louis Oosthuizen.
Thomas' birdie putt wasn't the first remarkable moment the 24-year-old American has given us this year.
Thomas held off the challenge of his rivals in the closing stages to finish at eight-under par for the tournament. How much did that come from Erin Hills and what you learned there, and how much is that just the state of your game and how you felt?
He had one blemish - a double bogey on the seventh hole - in an otherwise bogey-free round that included three birdies.
"I can feel my left rhomboid going into spasm", he said.
"That really, really hurt not making that team", he said in January, per GolfChannel.com's Jay Coffin. You might not see my until next year.