The mile, or its metric equivalent, the 1500m, is a glamour event of track and field and Walker was invariably a major drawcard at any athletics meeting. He was a track and field rock star. He was bigger than most of his rivals and cut an impressive figure as he burnt up the tracks of Europe, his long, flaxen hair trailing behind him.
* Won the 1976 Montreal Olympic 1500m gold medal.
* Became the first person to break 3min 50s for the mile, setting a world record of 3min 49.4s.
* Set a 2000m world record that lasted a decade.
* Ran more than 100 sub-four minute miles, the first person to reach that milestone.
* Won three Commonwealth Games medals.
Walker was one of three big-name New Zealand distance runners who emerged at about the same time. With Dick Quax and Rod Dixon, he blazed a trail through Europe throughout the 1970s.
His first sub-four minute mile was at Victoria, Canada, in July 1973 when he blitzed a B section field and stamped himself as a champion in the making.
Walker beat Bayi in Europe the next year and also turned in a 3min 32.4s 1500m. The world eagerly awaited a Walker-Bayi showdown at the 1976 Olympics.
In 1975, Walker was supreme. He ran eight sub-four minute miles and won them all. The big one was at Gothenburg, on August 12, when he thrilled 11,000 spectators with a stunning display of power and speed. He surged across the line and into the arms of the other New Zealanders at the track - Dixon and journalist Ivan Agnew, who told him excitedly he had gone under 3min 50s.
Track & Field News named him as Athlete of the Year for 1975.
The following year, though beginning to be hampered by a leg problem that was eventually to require an operation, Walker was again in a class of his own. He rated his 2000m world record of 4min 51.4s at Oslo that year as the best he ever ran.
At the Montreal Olympics, Walker caused his supporters some flutters when he was eliminated early from the 800m, but in the 1500m - in a field weakened by an African boycott - he was always the man to watch. After a slow early pace in the final, he was faced with the prospect of having to outkick runners who were faster over 800m and made his bid with 300m remaining.
Leg injuries handicapped him and stomach cramps forced him to cut out the longer distance work in his training. Yet took a silver medal behind Englishman Steve Cram in the 1982 Brisbane Commonwealth Games 1500m, then flirted, with moderate success, at the 5000m at the 1984 Olympics and 1986 Commonwealth Games.
In 1990 he made the final of the Auckland Commonwealth Games 1500m, only to be tripped early in the race. Afterwards he did a victory lap at the invitation of the gold medallist, Englishman Peter Elliott.
Walker hoped to become the first person to break four minutes for the mile after turning 40, but his attempt had to be called off because of a leg injury.
Walker was awarded the Lonsdale Cup in 1975 and 1976, was inducted into the New Zealand Sports Hall of Fame in 1990 and eventually the Mt Smart Stadium track in Auckland was renamed John Walker Track.
He received a New Zealand 1990 Medal and in 1996 the International Olympic Committee presented him with the Olympic Bronze Order.
He and his wife Helen, who have four children, run an equestrian shop just south of Auckland and he has been a long-serving member of the Manukau City Council. He has maintained his links with athletics as a television commentator, working for Australian and New Zealand channels.