After Thomas finished a shot out of the playoff between Harris English and Joaquin Niemann on Sunday - one that English ultimately won - he spoke briefly with Golf Channel and further addressed his error.
He had the ball.
English was the third-round co-leader at 21-under, but he was even par through 11 holes on the Plantation Course at Kapalua in Maui and had to chase down Niemann, who closed with a 64.
"Like I said, it's in excusable". "Usually, being four back going into Sunday I'm thinking about one thing and one thing only and that's trying to win the golf tournament".
It didn't take long for Thomas to assert his dominance this time around. "You've got to have confidence in yourself".
But he missed a 6-foot birdie putt on the 18th that cost him. A full swing with a lob wedge only got it up the hill to the fringe, and his birdie attempt from 15 feet was short.
'It's inexcusable. First off, I just apologise. It was the second straight year the tournament was decided by a playoff. He played so well from there that he reached the Tour Championship, and it paid off in a big way. To finish third at 24 under a year later speaks to the quality of golf at Kapalua this week. Niemann also didn't win a year ago.
The fact English made it to the Tour Championship was proof of turning around his game.
The three-time Major champion has not won since claiming the Open Championship in 2017 and had only two top-10 finishes previous year, failing to finish better than a tie for 46th in any of the three Majors. "It's awesome to get some validation".
Cameras picked up world number three Justin Thomas using a homophobic slur after missing a putt on Saturday. He missed the eagle putt but tapped in for birdie to close at 4-under 69 for the day and 25 under for the tournament. A birdie on the final hole wasn't enough.
Dustin Johnson, playing for the first time since winning the Masters in November, charged to a 5-under 31 on the front nine before being derailed by a double-bogey on the par-4 12th. He shot 69 and tied for 11th, ending his streak of seven top 10s dating to the first week in August.
Justin Thomas started the final round of his Sentry Tournament of Champions title defense four shots back of the lead but with his mind in an unusual place. His hopes came undone when his tee shot on the par-3 11th turned left with the wind into the shin-high grass.
Thomas went 28 holes without a bogey before a lip-out on a six-foot par putt at 17 dropped him two adrift.