The Canadian men are one win away from qualifying for the Tokyo Olympics for the first time in 37 years. But standing in their way is "the giant in CONCACAF."

Canada faces host Mexico on Sunday in Guadalajara in the semifinals of the CONCACAF Men's Olympic Qualifying Championship, which determines which two countries will represent North and Central America and the Caribbean in Tokyo this summer.

"We're well aware of who the opponent is. It's the giant in CONCACAF," said Canada coach Mauro Biello. "For us, I think we're in a position where we wanted to be, in terms of now getting to that one game that allows us to go through to the Olympics.

"And we're looking at it as that. It's one game where anything can happen. We're preparing to play the giant."

Biello says his players are well aware of what's at stake at Jalisco Stadium.

"We had a meeting and a discussion with the players of how big this is for Canada," he said. "We're talking about probably one of the biggest achievements in Canadian soccer history -- to come through and win this game and go on to the Olympics, beating the best team in CONCACAF in their country. There's no doubt that this opportunity is massive, for the team and the country.

"And (Sunday) we not only represent the team but we represent a country that is behind us."

The Canadians will have to buck history to make it. Canada is 0-4-2 against Mexico at the under-23 level in CONCACAF Olympic qualifying since 1992.

No Canadian men's team has ever beaten Mexico in a competitive match on Mexican soil, although Canadian youth teams have twice won friendlies there (in 1982 and 1986).

"These stories have happened in sports and it's a David and Goliath story going on right now," Biello said.

"We'll be going into the game obviously knowing we're the underdogs. But we're going to feed off that," added Canadian goalkeeper James Pantemis, who has recorded two clean sheets at the tournament. "I think it would be a fantastic story, not only to qualify for the Olympics but to take down the hosts. So that's what we're looking to do."

Mexico has dominated men's youth play in CONCACAF in the past. The Mexicans went unbeaten in all CONCACAF youth competitions (U-17, U-20, U-23) across eight years and 44 matches (39-0-5) from March 2009 to February 2017, winning seven CONCACAF youth tournaments along the way.

Sunday's semifinal showdown matches Canada's stingy defence (one goal conceded in three games) against Mexico's potent offence (eight goals in three games).

The Mexican attack features 23-year-old Uriel Antuna, who has scored eight goals in 16 games for the full Mexico national side, and 22-year-old Roberto Alvarado, who has three goals in 20 senior appearances.

Biello pointed at the Mexicans' speed in transition, saying his team can't give them space.

"They're a team that's going to make you pay. In the (final Group A) game against the Americans, one mistake out of the back and it was in the back of the net. They have that quality, for sure. They have that experience."

Canada (1-0-2) finished second in Group B behind Honduras on goal difference after the two teams played to a 1-1 draw Thursday. Mexico (3-0-0) won Group A with a 1-0 win Wednesday over the U.S.

The Americans (2-1-0) face Honduras (1-0-2) in the earlier semifinal Sunday.

While Canada has not qualified for the Olympics since 1984, the other three semifinalists have made a habit of getting there.

Of the 16 Olympic slots open to CONCACAF since the 1984 Games in Los Angeles, Mexico (five appearances), the U.S (5) and Honduras (4) have occupied 14 of them. Mexico won gold in 2012 in London while Honduras was fourth at the 2016 Games in Rio de Janeiro.

The CONCACAF qualifier was originally scheduled for last March but was postponed due to the pandemic. Despite the year's delay, the competition proceeded with the same age limit that players had to be born after Jan. 1, 1997.

Pantemis called competing at the Olympics "an athlete's dream."

"Just the fact we're 90 minutes away from it, regardless of the team that we're facing, it's just one game, 90 minutes," said the 24-year-old CF Montreal 'keeper. "I have a feeling that if we put everything out there, we leave it all out (there), guys are playing for each other, working together, we have a chance to make history and make the country proud."

Breaking Mexico down won't be easy. The host country has conceded just one goal at the tournament while Canada has scored just three.

Biello says the space has been there for his team to attack but the timing or quality of the delivery was off. He said his team will have to take advantage Sunday.

"It has to come together in a game like versus Mexico because the chances won't be there," he said.

Fatigue is an issue with Sunday's match Canada's fourth in 10 days. The Mexicans started tournament play a day earlier and so had an extra day's rest before the semifinal.

Canada captain Derek Cornelius, the Vancouver Whitecaps centre back who came off in the 73rd minute with an apparent leg injury against Honduras, should be available Sunday, said Biello.

Canada is short in central defence with Thomas Meilleur-Giguere injuring his knee on the eve of the tournament and Callum Montgomery going down in the first game.

ESPN, meanwhile, reported that FIFA has opened an investigation after anti-gay chants were heard during the March 18 game between Mexico and Dominican Republic.

"We'll see how it goes. It didn't happen in our games," said Biello. "So I guess it's in FIFA"s hands right now."