Kirk edges Cole in play-off for PGA Honda Classic victory
It was an emotional win for the 37-year-old American, whose last victory at Colonial in 2015 was followed by time away from the game in 2019 to deal with depression and alcohol misuse.
He took a two-shot lead into the final round and carded a one-under-par 69, shaking off a bogey at the 72nd hole with a birdie when they returned again to 18 for the first hole of the playoff.
There Kirk spun his approach within a foot of the pin while Cole was in a greenside bunker and missed a 10-foot birdie attempt to extend the playoff.
"I just have so much to be thankful for," Kirk said. "I'm so grateful. I'm so grateful for my sobriety. I'm so grateful for my family. I'm so grateful for everyone that's supported me throughout the past three or four years especially."
Cole, who is a US tour rookie this season at the age of 34 - and with 56 professional wins behind him on the Minor League Golf Tour mini-tour - carded a final-round 67 on the par-70 PGA National course in Palm Beach Gardens, Florida, where he joined Kirk in finishing with a 72-hole total of 14-under par 266.
He and Kirk duelled all day and finished two strokes in front of third-placed Tyler Duncan, who carded a 66 for 268.
Kirk got off to a quick start, rolling in a 17-foot birdie putt at the opening hole.
After a bogey at the second, he got up and down for a birdie from a greenside bunker at the third and rolled in a 34-foot birdie at the eighth to take a two-shot lead.
Cole had kept in touch with birdies at the third, fourth and fifth - where he snaked in a 70-foot putt.
He was in the water for a bogey at the sixth, but after a birdie at 11 pulled him back within one stroke he grabbed the outright lead at the 13th as he rapped in a seven-foot birdie putt while Kirk bogeyed.
Cole gave back a stroke with a bogey at 15, where he needed two shots to get out of a greenside bunker, and Kirk regained the solo lead with a 19-foot birdie at the 16th.
Cole hangs tough
Kirk couldn't close it out at 18, however, as his second shot from the fairway found the water and he was unable to convert a 16-foot par-saving putt.
"I was obviously very, very nervous today having not won in so long," Kirk said.
"Coming down the stretch, I felt good. Obviously that putt on 16 was huge and was in a great position on 18, just made a bad swing at the wrong time."
Cole, who is the son of former PGA Tour player Bobby Cole and former LPGA player Laura Baugh, called it a "great week overall."
"I felt like I hung pretty tough, and I was really proud of that," he said.