And the Canadian women rose to the occasion Sunday after an uneven group stage, taking it to the 19th-ranked Swiss in the second half before 53,855 at B.C. Place — a record for a Canadian national team home game.
Herdman, a master manipulator, pulled all the right strings Sunday.
The winning goal came in the 52nd minute from Josee Belanger, a forward Herdman had convinced to rejoin the national program. And it came from a cross delivered by fullback Rhian Wilkinson, restored to the starting lineup by Herdman after a hamstring injury.
Belanger had served as a make-shift fullback in place of the injured Wilkinson and Marie-Eve Nault in the first three games of the tournament.
Captain Christine Sinclair served as a key link-up for the goal, fighting through traffic to get a foot to Wilkinson's cross and poke it over to Belanger, who thumped a left-footed shot past Swiss 'keeper Gaelle Thalmann.
It was the turning point of the game, capping an explosive Canadian start to the second half. The first 45 minutes were fairly even but the Swiss had started to make inroads into the Canadian defence, with the elusive Ramona Bachmann probing the backline.
Canadian goalkeeper Erin McLeod said Herdman reminded the players at halftime that there was no going back.
"He just put it pretty simply. He just said 'We can't have any regrets ... This second half we're going for it.' And everybody did," she said.
Canada came at the Swiss in waves to open the second half. And the young European team seemed to wither under the pressure, although it came back in the final minutes in search of the tying goal.
McLeod, as she has done all tournament, made a key save in the 77th minute to deny Vanessa Bernauer from in close. She has kept three clean sheets in four games, conceding just one goal.
"I'm really proud of the way the team performed," said McLeod. "I think in the second half especially we played like the Canada I know and that we're going to show a lot of more at this tournament."
Next up for eighth-ranked Canada is either No. 6 England or No. 11 Norway in Saturday's quarter-final at B.C. Place. The two European teams face off Monday in Ottawa.
Canada will go into the game having finally dispatched a European team at the tournament. Its record against European opposition at the World Cup prior to Sunday was 0-9-1.
"Proud of my girls," said Herdman. "Proud of what we've been able to achieve. We've got more tough opposition coming."
The Canadian women showed their grit en route to the win.
Teenage defender Kadeisha Buchanan played with a strained abdomen while midfielder Sophie Schmidt, who suffered a bruised hip in the last group outing against the Netherlands, had a pain-killing injection before the game.
Herdman said Buchanan, who hadn't trained for three days, almost didn't start.
"She had a few tears before going out because she's hurt. But she played out there like a warrior today."
Belanger was out of the national team picture from early 2011 to late 2013, missing out on the 2011 World Cup and 2012 Olympics. A longterm ankle injury disrupted her career and, disillusioned with her experience with a previous national team regime, she was thinking of moving on and starting a family.
So Herdman, in need of pace and goals, went looking for Belanger.
"We tried everything. She was, I think, ready to settle down and we talked her back into the program," he said.
It was more difficult that it sounds.
Herdman, who comes from just outside Newcastle in northern England, first called Belanger's house and got her French-speaking mother. Then he flew to Quebec to speak at a coaching conference and, knowing Belanger was in the audience, called her out.
"Look your country needs you," he said.
Belanger's memory of that day? "I remember I couldn't understand his accent," she said with a laugh.
"It was a big step for me to forgive the past, come back and let it go," she added.
She eventually came round — it helped that a new, supportive boyfriend encouraged her to follow her dream. Herdman recalls that she dribbled past four players and scored in her first practice back.
The dividends continued Sunday with her sixth goal for Canada — and first since December 2010.
Bachmann came as advertised, full of pace and knowing what to do with it. Fortunately Canada had Buchanan, a teenage stopper who was called upon to clear up a few defensive messes not of her own making.
The Swiss came forward in the dying minutes but could not break down the Canadian defence.
"Canada had the momentum and they scored the goal so congratulation to Canada," said Swiss coach Martina Voss-Tecklenburg, through an interpreter.
The former German international took the time to thank Canada for its hospitality.
"You're an amazing country," she said.
The Swiss made it to the knockout round in their first time at the World Cup.
It's just the second time in six trips to the tournament that Canada has made it to the knockout rounds. The Canadians finished fourth in 2003.
For Sinclair, Sunday offered more signs of Canada at full throttle.
"Throughout the course of this tournament I think we've shown glimpses of what we're capable of," she said. "The start of the second half (against Switzerland). Against Holland the first 20 minutes of that game.
Canadian midfielder Kaylyn Kyle entered the game in the 76th minute, earning her 100th cap.
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