Herdman, who played for his university as well as semi-pro teams back home in England, has a sense of humour. He also likes his party tricks on the ball.
"He does have some moves," said veteran midfielder Diana Matheson. "The Black Flash's downfall is that he maybe uses too many moves and he gets himself into trouble and maybe causes a few goals against his team that way."
But most of all, Herdman is a master motivator and source of inspiration, his players say. No one works harder or longer.
They say Herdman has made them better players and better people.
Those skills will be put to the ultimate soccer test starting this weekend — the Women's World Cup. Canada, ranked eighth in the world, opens Saturday against No. 16 China at Commonwealth Stadium.
Herdman's journey with the Canadian women started when he took over from Carolina Morace in the wake of a disastrous 2011 World Cup that saw Canada finish last.
Ask the players what state they were in after the tournament in Germany, almost every one uses the same word. Broken.
When Herdman coached the New Zealand women, his team was bound together by the Maori heritage. The Football Ferns had a Maori spiritual leader.
One of his mentors told Herdman he needed to find a way to get the Canadian team reconnected after the "trauma" of the 2011 World Cup. In doing his homework, Herdman was struck by Canada's patriotism.
"My first piece was like 'Who are you as Canadians?' That was my first question. Tell us," said Herdman. "And we went 30 minutes in a meeting. They'd never been asked that before by a Norwegian or an Italian coach.
"They had never been asked anything about why they do what they do. What do you do it for. Ever. Can you believe that? In your career you've never been asked why you do it, and you wonder why they failed. Because they've just been putting that jersey on. And once they'd earned it, after a while it just become normality. 'Put this on. Why do we do this. Well, represent Canada.'"
In Canada's final warmup game last week, every member of the match-day squad took the field for the anthems before facing England in Hamilton. They put their arms over their neighbours' shoulder and sang "O Canada" together. Only the English starters were on the field.
Herdman and his management team leave no stone unturned. They have everything from game formations for every situation to driving times from the team hotel to stadium down pat.
The 39-year-old Herdman is a stylish, compact package. In a black tracksuit, he can look like an Italian movie star slumming.
He loves family, music — something is always playing in the background when he meets with the team — and his beloved vintage VW Bug. And his energy and enthusiasm seems boundless.
A former university lecturer in England, he is cerebral but able to connect. In many ways, he's a Geordie Tony Robbins, pushing his charges to improve and connect on and off the field.
In one sense, he has already succeeded. This Canadian women's team is about as interesting a group of athletes as you can meet.
Unlike their male counterparts, there is no sweetheart contract waiting for them. And so while full-time athletes, they have expanded their horizons. Chiropractor, fitness DVD guru, artist, Zumba instructor, food truck owner and documentary video-shooter are just some of their off-field pursuits.
Herdman has challenged his players to become true leaders, a subject they have literally studied off the field through books and lectures. He has had them strip away defence mechanisms to share their emotions with their teammates, further strengthening team ties.
Ask his players what it like working under Herdman and they say it's an honour and a privilege.
"(He's) somebody that knows absolutely how to get the best out of people," said veteran defender Carmelina Moscato. "He's a high-performing guy. He's created the environment for that. And you talk about squeezing blood from a rock, I mean he's really done it with a lot of us — reinventing us.
"I'm 31 years old and he continues to call me a modern centre back. So I'll take it. It's pretty awesome."
"It's incredible what he's able to get out of people, not just his players but even the staff," said 17-year-old midfielder Jessie Fleming.
"John has affected all of us in huge ways and only a tiny piece of that is soccer-related," said 33-year-old fullback Rhian Wilkinson. "It sound ridiculous but he's changed me probably as a person and I only met him when I was 29."
"An incredible man and an incredible coach," she added. "We're very very lucky to have him but also to be able to listen to him day-in and day-out."
"He's a great leader, very motivational," said midfielder Sophie Schmidt. "And he has an inspiring way of bringing out the best in us and wanting us to be the best."
"The best coach I've ever had," said forward Jonelle Foligno.
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