Jason Day is overcome with emotion after winning his first major title

The most remarkable part about Jason Day finally winning a major championship was that it was hard to decide which aspect of it was most remarkable. It was either that he once was a troubled 12-year-old at a golf-oriented boarding school, that he kept losing majors at the end or that he was playing against Jordan Spieth, the best and most clutch player in golf today.

What he figured, after having the round of his life to win the PGA Championship on Sunday, was that it has been quite a life.

"It's just an amazing feeling that I have," he said after finishing at 20 under par, the best score in relation to par that anyone has ever had in a major.

"The path that I was on was never expected for me to be where I was today," said the man holding the weighty Wanamaker Trophy, having shot 5-under 67 to defeat Spieth by three strokes.

Day, 27, an Australian, had always dreamed about what it would be like to win one of golf's four great tournaments. He said the reality was different from what he had envisioned. "I didn't expect I was going to cry," he told the crowd around the 18th green at Whistling Straits.

He had good reason, starting with the most recent heartaches. He overcame a wild bout of vertigo at the U.S. Open to hold a share of the lead after 54 holes but fell short. Then he was within range of making the playoff at the British Open last month but left his birdie putt short. Even worse was the memory of leading the 2013 Masters with two holes to play, then losing to countryman Adam Scott.

All of that went through his head Sunday. "Knowing that I had the 54-hole lead or tied for the 54-hole lead for the last three majors and not being able to finish, it would have been tough for me mentally to really kind of come back from that," he said.

But the emotions that spilled out Sunday ran deeper than overcoming those failures. His tears recalled being a 12-year-old whose father had just died of stomach cancer and whose mother could not keep him out of trouble. She sent him to Kooralbyn boarding school, where Day immediately (and profanely) got into an argument with golf coach Colin Swatton.

"It's pretty well documented that Jason could have ended up on the wrong side of the tracks. He could have easily gone the other way. He wouldn't have been on the 18th green at Whistling Straits," said Swatton, who has since become Day's surrogate father, swing coach and caddie. He walked up to that 18th green with him Sunday and cried just as much.

Swatton was a proud caddie, having made the right choices, watching his boss sink a pivotal 49-foot, 5-inch birdie putt on No. 7, and proud coach, seeing Day's swing hold up as he boldly hit driver on many holes.

"We had a little disagreement initially, but from that day forward, we were a really good team," Swatton said, recalling the boarding school days.

"If you gave him something to do, he would just do it. He wouldn't question why, he wouldn't do it for a day or two days and then move on to something else. It was just, 'I'll do it until you tell me to stop. Just keep telling me to do what I've got to do.' ''

On Sunday, Day shrugged off a terribly chunked wedge shot on No. 9 and overcame a bogey on No. 15 with a birdie on the next hole, staying three ahead of the world's No. 1 player. "Each time he stood and took [his driver] back, I had hope," Spieth said. "And each time after it came off the face, the hope was lost."

Day's wife, Ellie, to whom he was introduced by Swatton, said her husband never lost hope through all of his disappointments. She noticed he was especially determined in the past few months. "This," she said, "had to happen. I've never seen anybody work harder, in every single way."

"This" meant Day had come a remarkably long way to walk those last steps. "I enjoyed the 18th hole when I had about a half-foot putt," he said. "So that was fantastic. It was a fantastic day for me personally and something I'll never forget."