Cyle Larin celebrates with his team-mates after opening the scoring in Canada's 2-0 World Cup qualifying win over the United States

Canada coach John Herdman has warned his team against complacency after they moved to the brink of a first World Cup appearance since 1986 with an emotional victory over the United States.

The Canadians have surged into a four-point lead at the top of the CONCACAF qualifying competition, leaving them near-certainties to grab one of the three automatic World Cup berths available to teams from Central America, North America and the Caribbean.

Three more points on the road against El Salvador on Wednesday could well leave them needing only a point from their final three fixtures in March to clinch a place at this year's finals in Qatar.

Amid the euphoria of Sunday's 2-0 win over the United States, which has left the Americans' own World Cup hopes delicately balanced, Herdman was quick to emphasise that nothing would be taken for granted until qualification was mathematically certain.

"We're not qualified yet," the 46-year-old Englishman said.

"The first thing we said when we brought the boys off the field was 'It's not done yet, it starts again tomorrow'. We're not there yet. We need some more points.

"I won't let these boys off the hook. So let's not get too far ahead of ourselves."

It would take a monumental collapse, and a freakish combination of results, to deny the Canadians now though.

On Sunday, goals from Cyle Larin and Sam Adekugbe earned Canada a clinical 2-0 win that embodied the strengths of Herdman's tight-knit, tactically well-drilled team, who were happy to cede possession for long periods and wait for openings on the counter-attack.

Herdman was also delighted by the raucous reception that greeted both team buses outside Tim Hortons Field before kick-off where thousands of Canadian fans had gathered.

Clouds of red smoke from flares drifted through the air while a profanity-laced chant of "We burned the White House to the ground" to the tune of "She'll be coming round the mountain" could also be heard.

- 'Wild mosh pit' -

That was music to the ears of Herdman, a Geordie and staunch Newcastle United supporter.

"I've seen nothing like it," Herdman said afterwards. "It's everything I've dreamed of. I'm a hardcore Newcastle fan, a football fan at heart. 

"And I used to turn up to St. James Park and used to love that walk-in, sometimes that was my favourite part of the game - the atmosphere."

Herdman, who took over the Canadian men's team in 2018 after a successful stint in charge of the women's team, said Sunday's crowd scenes marked the "first time I felt I was living in a football country".

"The flares were going off, it was like Liverpool arriving for a Champions League game," he said. "It was that wild in that mosh pit. The bus couldn't even get through."

Herdman says Canada's success has ignited support across the country's diverse population, which in turn has energised his squad.

"This is what we've dreamed of – to get people excited," Herdman said. 

"You know -- the Canadian people who've always had to wear an Italian shirt or a Serbian shirt or a Greek shirt.

"They can put them down and pull on a Canadian jersey now and be proud of us as a football country. And when the boys feel it they're absolutely buzzing."

Herdman said qualification for the World Cup had been pinpointed as the goal of the squad at the "very first team meeting" when he took over four years ago.

But Herdman maintains qualification will have a seismic long-term impact for football in Canada, where ice hockey remains by far the most popular sport.

"We knew if we qualified we could change into a football country for ever," Herdman said. "And that's what's driven us every day. 

"It's what the players hear from me every meeting. It's bigger than us. It's way bigger than us.

"We all want to get to Qatar, that's one thing, and there are personal agendas to do that which is normal.

"But I genuinely believe these men know they've got an opportunity there to leave a proper football legacy for this country moving forward."