US coach Jurgen Klinsmann sees his team's struggles to advance from the semi-final round of World Cup 2014 qualifying as a sign of the improvements made by football rivals in North America.
The Americans are locked in a fight with Jamaica and Guatemala to decide two spots in next year's Confederation of North and Central American and Caribbean Association Football (CONCACAF) final qualifying round for Brazil's World Cup.
A US under-23 side failed to escape regional qualifying and missed the London Olympics, serving notice that an extension of America's run of World Cup trips dating to 1990 is not a certainty.
"What happened to the Olympic team was a huge warning to whoever thinks CONCACAF is an easy region to go through. Teams in CONCACAF have improved a lot," Klinsmann said.
"I speak with some coaches overseas and they say, 'You will go through with no problem at all.' I tell them, 'No, it's hard. Those teams you play against play with their heart and give their all. You have physical battles. You have to adjust to the environment. It's a difficult qualifying campaign. It's a marathon.'"
The Americans are deadlocked with Guatemala atop qualifying Group A at 2-1-1 on seven points, each with six goals scored and four allowed, while the Jamaicans are also 2-1-1 but rank third on lower goal difference.
The two top teams in each group advance to next year's final qualifying round.
On Friday, the US squad visits winless Antigua and Barbuda, while Jamaica will visit Guatemala. On Tuesday, the Jamaicans host Antigua and Barbuda, while the Americans will host Guatemala at Kansas City, Kansas.
"Antigua will fight for every ball. They will give everything. And the same will happen with Guatemala," Klinsmann said. "We have to give everything we have. We have to build in a sense of urgency and be prepared for the challenge."
And the Americans will be without injured striker Landon Donovan, the all-time US leading goal scorer, and Jozy Altidore, the hot striker for Dutch side AK Alkmaar who was not called up for the matches.
Klinsmann is taking nothing for granted on the US trip to Antigua.
"Anything can happen in Antigua in terms of the field and conditions," he said. "We need to find ways to break them down and score goals.
"This will not be an easy game. For them, this will be the game of the decade. They want to prove everything against the US. We have to go in with the right mentality and take care of it."
Unbeaten Mexico has already qualified from Group B, but Klinsmann is not concerned about matching the flair the US arch-rivals have shown.
"We would love to play very well but first we have got to make sure we score the goals," he said. "You have to find a way to break them down and it's not always possible to look good doing it."
El Salvador will play host to Costa Rica in a match-up of the top contenders for the other Group B berth on Friday, while the Mexicans visit winless Guyana.
In Group C, leader Panama can clinch advancement with a home victory over Honduras, while already-eliminated Cuba visits contending Canada.