When Fox rolled in a 12-foot birdie putt on the 18th hole at Royal Birkdale to win The Open Championship by one shot in Southport, England, it was just past 5.30am in his homeland and the sun hadn't yet risen.
Most New Zealanders awoke on Monday to a wintry morning and the news of Fox's incredible breakthrough transcended the sports-mad country.
Sir Bob Charles, New Zealand's first major winner and the first left-handed golfer to land a major when he won the 1963 British Open, is now 90 and watched Fox's round in replay at a more congenial hour.
"I'm watching this in colour. In my day, it was all black and white," Charles told the New Zealand Herald newspaper.
Charles praised Fox for the pace at which he plays the game that goes against a modern tendency toward slow going. Fox hesitated for barely 30 seconds over the final putt that allowed him to join Charles, Michael Campbell and Lydia Ko as a Kiwi major winner.
"Ryan is a refreshing player," Charles said.
"He plays the way the game should be played, the way it used to be played and should be played. And that is: you get on with it, and you don't spend half an hour lining up every putt."
New Zealanders rushed to social media to praise the 39-year-old Fox, a third-generation sporting champion within his family. His father, Grant Fox, was an All Blacks rugby star and winner of the 1987 Rugby World Cup. His grandfather, Merv Wallace, was a captain of the New Zealand cricket team.
Fox touched on the family history after his win.
"We've got a great history in our family," he said. "The other great thing is I had no pressure on me to follow in any of their footsteps. I don't know if this tops their achievements, but it's certainly right up there. I guess there's no pressure on my kids going forward now."
At Fox's home course, the Royal Auckland and Grange Golf Club, club captain Ian Blair said "you couldn't find a nicer guy and more worthy champion golfer".
"Our club has been privileged to watch Ryan develop from a fine young man with potential to a champion player and member," Blair said.
Club chief executive Ian Chapman told the Stuff news website members would be queuing up to buy Fox a beer.
Campbell, the 2005 US Open champion, described Fox's effort as "an incredible feat ... to beat the world's best players in a difficult situation."
"I got to experience that 21 years ago. It's mind-blowing. It really changes your world and he's up there with the best players in the world now," Campbell said on the New Zealand Herald's Ryan Bridge today podcast.
Even the Wallabies' outgoing Kiwi coach was left in awe.
"It's huge," Joe Schmidt said after staying up half the night in Sydney to watch.
"It was outstanding for him to get there. What Ryan Fox has done is incredible.
"Obviously I know his dad better than I know Ryan. But having a dad who's an iconic rugby legend in New Zealand and he's well and truly out of the shadow.
"It's great for the game in New Zealand. It's great for Ryan Fox, obviously, and it's a nice change up in terms of majors, where they tend to be dominated by similar sort of people."
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