Australia's sporting fraternity saluted Jason Day's victory in the PGA Championship as a triumph over adversity.

Day is the fifth Australian to win the PGA title and the 12th to win a major championship — the first since Adam Scott in the 2013 Masters.

After Day closed with a 5-under 67 at Whistling Straits for a three-shot victory and a majors-record 20-under total, Australian tennis and cricket players and racing drivers were among those quick to congratulate Day.

Growing up in the regional Queensland state towns of Beaudesert and Rockhampton, Day lost his father, Alvin, to cancer when he was 12 and battled alcohol and aggression at a young age.

It was Alvin who enrolled Day as a junior member at Beaudesert Golf Club at age six and gave him his first golf club, but it was mother, Philippines-born Dening, who — worried at her son's increasing waywardness — later scraped together the money to send Day a few hours away to board at Kooralbyn International School and then Hills International College.

At Kooralbyn — which had a golf course attached to its grounds — Day met coach Colin Swatton, who has been both caddie and confidant throughout his professional career.

After Kooralbyn closed, Day and Swatton moved to Hills International College, which had a dedicated golf program. It was there that Day borrowed a book about Tiger Woods from a roommate and was spurred to take his golf even more seriously, practicing up to 30 hours a week.

Dening Day was at work and missed watching the final holes of the PGA Championship, relying instead on updates on the PGA website.

"It takes a long time before it gets updated," she told Australian Broadcasting Corp. radio Monday. "It gets a little bit anxious."

That anxiety turned to elation when it became clear what Day had achieved.

"I was so excited, I was so proud of him," Dening Day said. "It has been a long time coming for him. It's a culmination of all his hard work."

Day expressed his own relief that he would no longer be known as the best golfer not to win a major, tweeting "Ding, dong the witch is dead" after the victory.

Congratulations came from contemporaries and compatriots.

Two-time U.S. Open champion Greg Norman wrote on Instagram "congratulations to my fellow Queenslander and Australian (Jason Day) and his beautiful family Ellie and Dash for joining the elite club being a major winner."

Tiger Woods posted on Twitter "game over, very happy for Jason. Great dude and well deserved."

Sydney Morning Herald golf writer Matt Murnane said that with his win in the final major of the year, Day "becomes a legitimate contender, alongside the game's other under-30 superstars, world No. 1 Spieth and No. 2 McIlroy."

To add to his early trials, Day lost eight family members in the Philippines to the devastation wreaked by Typhoon Haiyan in 2013, then collapsed on the course during the U.S. Open because of an ongoing illness.

Writing in Queensland's Courier Mail newspaper, Jim Tucker said "all the armor-plating from the near misses and the heartbreaking losses from Day's past surfaced to produce a true major champion.

"The popular Queenslander, who first grabbed us for a roller coaster run at the 2011 Masters at Augusta when he finished a heartbreaking second in his first major, has deserved this."