Famed New Zealand Olympic distance runner Sir Peter Snell is being remembered as "the greatest athlete New Zealand has had" following news of his death at age 80.
Sports historian and friend Ron Palenski confirmed to the Herald Snell had died at his home in Dallas after years of heart problems.
Palenski said Snell's wife Miki phoned him this morning to share the sad news.
The couple had been planning to go shopping on Thursday at noon Dallas time, when Snell "nodded off to sleep".
"Miki was getting ready, and Peter nodded off, as is not unusual for him. But he didn't wake up."
Snell had been going to cook a roast for dinner and had talked to Miki about the possibility of playing table tennis.
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Palenski said Miki told him: "But I want people to know that he was living his life. He was not bed-ridden."
Snell was due to turn 81 on Tuesday.
He is one of New Zealand's most famous Olympians, winning three gold medals - the first for the 800m at the 1960 Rome games, then in both the 800m and 1500m in the 1964 Tokyo games.
Born in Taranaki, his family later moved to Waikato, before he completed his schooling at Mt Albert Grammar in Auckland.
By the age of 19 he was concentrating on athletics.
Palenski, chief executive of the New Zealand Sports Hall of Fame, was a friend of Snell's and had worked with him a lot over his career in his journalism and writing.
"It is very sad news, a grievous loss for New Zealand.
"In terms of track and field, he is probably the greatest athlete New Zealand has had.
"He is up there with those figures like Sir Edmund Hillary, Sir Brian Lochore, who rose beyond their great achievements.
"But at the same time [Snell] was a very humble guy. He very reluctantly talked about himself. In Dallas, people didn't know who he was, because he didn't tell them."
One of Snell's friends and fellow New Zealand Olympic teammate, Barry Magee – who won bronze in the marathon at the 1960 Rome Games – paid tribute to him this morning.
He said Snell would go down as a once-in-a-lifetime Kiwi athlete.
"There will never be another New Zealand athlete like him," Magee said.
"He won three Olympic gold medals, two Commonwealth Games gold medals and broke seven world records. He was the best-conditioned athlete of his time."
Magee, 85, was one of Snell's long-time training partners, and a teammate in the New Zealand Olympic team.
When Snell donated some of his racing memorabilia to Te Papa in 2017, he paid tribute to Magee.
"He thanked me ... I ran the most amount of miles with him during his training," Magee said.
"He said he probably wouldn't have won his medals without me.
"His death will be very big news [around the sporting world]. The sports writers won't know where to start [with tributes]."
Magee said while he was "in shock" over his mate's death, he was well aware of the health problems Snell had faced in recent years.
"He had a pacemaker fitted about five years ago," Magee said.
"And his recent issue a few weeks ago was probably a warning. It just goes to show that health is wealth."
Fellow Kiwi athletics great and Olympic champion Sir Murray Halberg was not available to comment today.
But in a statement, the Halberg Foundation said: "The Halberg Foundation and our founder Sir Murray Halberg along with Lady Phyllis Halberg is saddened by the passing of Sir Peter Snell.
"Sir Peter was a legend on the track – and recognised as the 1960s Halberg Awards Decade Champion and Sports Champion of the Century for his outstanding achievements.
"He will also be remembered as a gentleman off the track and a dear friend to Sir Murray who says he has enduring memories of the Olympics and touring throughout Europe together.
"Our thoughts are with all of Sir Peter's family."
Kiwi athletics legend Rod Dixon posted a tribute on social media, saying he was "absolutely devastated".
"Lost my friends Dick Quax and Graham Crouch and today's call was a shock. Peter Snell is New Zealand's Greatest 800-1500 Olympian of all time. Blessings to Miki."
Snell had a serious heart scare while driving last month. He told the Herald he was thankful he "didn't kill someone".
The champion, who developed heart problems in 2010, said: "What it does is the [heart] rate goes up too high and that causes me to pass out. That may be because I failed to take my pills that morning."
Snell was due to appear at the World Athletics Heritage Mile Night in Monte Carlo that week and even attempted to defy doctors' orders to attend the event, but decided against it at the last minute after "feeling poorly" at the airport.
"Yeah, I was actually packed and all ready to go," Snell said.
"But I waited and sat down with my wife and we decided the way I'm feeling that it would be too risky to take the flight because if I had an event on the flight there would be nothing I could do about it."
He was going to be presented with two "surprise" world record plaques at the event in Monte Carlo for 1000m and one-mile records he set in Auckland.
Despite being disappointed he couldn't make the awards event, which featured eight of the last 10 living men's outdoor world record holders, Snell was in good spirits and feeling a lot better after resting at home.
"I'm feeling much better because my potassium is now normal … But I don't think I would've been enjoying myself too much in Monaco."
In 2010, he told the Herald he could have died the previous year after blacking out for up to 15 seconds.
He had been fitted with a pacemaker/defibrillator device on the recommendation of his cardiologist, after being diagnosed with a weakened heart that could no longer pump blood efficiently - because of a condition officially know as idiopathic dilated cardiomyopathy.
He was also on drugs to lower his blood pressure and reduce arrhythmia.
After his success at the Perth Commonwealth Games, he was appointed a Member of the Order of the British Empire for services in the field of athletics in the 1962 Queen's Birthday Honours.
Three years later he was elevated to Officer of the same order in the 1965 New Year Honours.
In the 2002 New Year Honours, he was appointed a Distinguished Companion of the New Zealand Order of Merit for services to sport, and in 2009, after the restoration of titular honours by the New Zealand government, he was redesignated a Knight Companion of the New Zealand Order of Merit.
In 2007 he was awarded an honorary doctorate (DSc) by Massey University in recognition of his work as an exercise physiologist.
A larger than life-size bronze statue of Snell was erected in his hometown of Opunake, Taranaki, in 2007.
The statue is based on a photo of Snell crossing the finish line in the historic race at Wanganui's Cook's Gardens in 1962. A similar bronze statue of Snell was unveiled in Cook's Gardens in 2009.
After his running career, Snell worked for a tobacco company before moving to the United States in 1971 to further his education. He gained a B.S. in human performance from the University of California, Davis, and then a Ph.D. in exercise physiology from Washington State University.
He joined the University of Texas Southwestern Medical Centre in 1981. He was an associate professor at the university's Department of Internal Medicine and director of its Human Performance Centre.
Snell also adopted other sports after his running career. He became an active orienteer and won his category - men aged 65 and older - in the 2003 United States Orienteering Championship.
He also became a competitive table tennis player, playing in US tournaments, and competed in the 2017 World Masters Games in Auckland.