One of his first cars was a silver Bug. He used to drive back and forth every weekend from university in Leeds to Consett in northern England to see his childhood sweetheart, now wife Clare. It helped that his best man was good at fixing Beetles.
Then someone drove into the back of it, totalling the car. Herdman told his wife that some day, when he had time, he would get one to work on with his son.
Years later, in 2014, he unearthed a 1962 ragtop in Abbotsford, B.C., that needed a ton of work. Then he found one in Toronto that was ready to go.
Herdman mulled over the choice. While the idea of working on the car with son J.J. was sweet, he knew that with his hectic schedule it would take decades to fix up.
So he bought the restored one, reasoning he and his son could share vintage car shows together (he also has a young daughter named Lilly-May). It's Herdman's everyday ride now, although the windshield wipers remain a bit dodgy.
It's a story that speaks volumes about the 39-year-old Herdman. It shows his style, loyalty and persistence, not to mention pragmatism.
Ask his players and they'll tell you the Canadian team was broken when Herdman took over in the wake of a last-place finish at the 2011 World Cup. The women were in a dark place, with players mulling over whether to walk away.
Herdman put the squad back together again, reminding them why they played soccer and for whom they did it.
The women rebounded from a roller-coaster semifinal loss to the powerful United States at the 2012 Olympics and defeated France in stoppage time to win bronze.
Now Herdman is plotting to turn heads on home soil as the Women's World Cup comes to Canada next month.
The compact coach grew up in Consett, just outside Newcastle. His father and both grandfathers were steelworkers, as was his wife's father.
Then the steel mill was shut down. His dad was one of the fortunate ones who found work in the oil industry in Scotland. As a teenager, Herdman did not see him much because he was away weeks at a time.
Herdman's dad had a mental breakdown and his parents split up. His older sister joined the RAF and at 16 or 17, Herdman found himself caring for his dad.
He has a brother eight years younger, who currently works as a coach in Newcastle United's development system.
Herdman grew up playing soccer, describing himself as an "OK" central midfielder. "You had to be more than OK to go and make it," he added. "It's every kid's dream there."
He went on to play semi-professional football in the Northern League and for his university, knowing that a pro career was not in the cards.
So he got into coaching, starting to take courses at 16. He had his own soccer school at 23.
At university in Leeds, he had met a teacher/businessman named Simon Clifford who was taken by the Brazilian style of football. So he went to South American to study Brazilian coaching methods, coming back to set up Brazilian soccer schools.
It appealed to Herdman, a slick player whose nickname when he takes part in Canadian team practices is The Black Flash.
At 22, he wanted to change English football.
Players from Sunderland started sending their kids to his school, which led to a job offer in the Sunderland academy. He spent three years there, working with a young Jordan Henderson, who is now a Liverpool star.
"He was class as a young kid. What a player," Herdman recalled.
At the time, Herdman was lecturing four days a week in the sports science department at Northumbria University and then going to the academy in the evening. His passion was the soccer side but he recognized there wasn't a future for those who hadn't played at the highest level.
Herdman thought about going for a PhD, using his experience at Sunderland as research. Then Dr. Paul Potrac, his supervisor at university, moved to Otago University in New Zealand.
Potrac told Herdman about a soccer job as a regional director in New Zealand, selling him on the chance to essentially take over a blank football canvas.
Herdman took him up on it, taking Clare with him and leaving the glitz of a Premier League club to settle in Invercargill, the southernmost city in New Zealand.
Herdman threw himself into the task, coaching all ages while creating a soccer blueprint for the region. As it is today, his passion was matched only by his hours.
"I can't remember when I haven't done an 80-plus-hour week," he said. "It's my personality, probably my mental disorder ... when I'm tuned into something I'm passionate about, I'm a bit crazy about it."
Herdman loved the job and people started to take notice of his work. In 2006, after four years in his regional development role, New Zealand Football picked him up and Herdman found himself again a jack of all trades after the federation went through a tough time and had to lay people off.
"At 29 years of age, 30, I was balancing nearly every ball in the organization."
When Australia moved out of the Oceania confederation to Asia, that opened the door for New Zealand to qualify for world championships.
The powers that be saw that the best chance for international success lay with the women, so they started investing in it. Herdman, who had enjoyed working with women in his regional director job, saw the possibilities.
He took the under-20 team to Russia in 2006 to the FIFA-20 Women's World Cup, tying Brazil.
He brought the U-20 side back to the world championship in 2008 and led the senior side to the World Cup in 2007 and 2011, making New Zealand soccer history along the way.
His last game at the 2011 World Cup was a memorable one. After losing 2-1 to Japan on a 68th-minute "stupid free kick" and then being knocked out of contention in a 2-1 loss to England on an 81st-minute goal, the Football Ferns rallied to score two stoppage-time goals to tie Mexico 2-2.
Herdman sees the game as a turning point, saying "it saved my career."
"The team was right on death's door and to get them up for that last game and for us to go 2-0 down, you knew you had to fight for their pride, you had to fight for your career, you were in it big-time."
He pounds the desk in satisfaction as he recalls the comeback.
After that World Cup, Canada offered him its job with the lure of a home World Cup prompting another move around the world.
"Coaching is my passion," he said at the time. "It's what I get out of bed for every day and this is an opportunity to do something special."
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