When the United States faces Group C leader Slovenia on Friday, the pressure is on the Americans.
Cushioned by three points from their opening win against Algeria, the Slovenes can afford to lose and still have a chance of advancing to the second round - albeit from a tough last group match against England.
For the Americans, who earned a surprising 1-1 draw with England in their opening match, avoiding a loss is more crucial.
"The game against Slovenia is going to determine if we get out of the group or not," U.S. defender Oguchi Onyewu said.
A loss would leave the Americans dangerously close to elimination. While a draw could be enough, the Americans need to beat Slovenia to enter the last group stage match against Algeria with any kind of comfort.
Slovenia, a nation with only 2 million inhabitants, is not at England's level in international football, but it has earned a reputation for producing upset wins over the bigger nations in crucial matches.
It stunned Russia in a two-match playoff to qualify for the World Cup. Romania and Ukraine have also missed major tournaments after stumbling against the Slovenes.
After losing all three matches in its only previous trip to the World Cup in 2002, Slovenia is already doing better this time around, thanks to captain Robert Koren's second-half goal against the Algerians.
Suddenly, advancing to the second round is not just a possibility, it's "our goal," Slovenia coach Matjaz Kek said.
"We have the opportunity to make our dreams come true already after the second game," Kek said Wednesday in comments translated from Slovene. "That would be a sensation, but I'm sure we are capable of it."
The Slovenes have sounded optimistic, even confident, that they can beat the U.S. Still, Kek said the Americans are coming into the match as favorites, given their higher FIFA ranking and the fact they made it to the final of the Confederations Cup last year.
The U.S. is ranked 14th, while Slovenia is No. 25.
Because Slovenia likely will rely on counterattacks, there has been speculation U.S. coach Bob Bradley might consider starting Jose Torres in place of Ricardo Clark in an effort to increase possession.
"That's what I do with my club team," said Torres, who plays for Eintracht Frankfurt in the Bundesliga. "I love controlling the ball and controlling the pace of the game."
Like the U.S., which equalized on a blunder by England goalkeeper Robert Green, Kek's team got a lucky break against Algeria as Koren's 79th-minute shot bounced in off the arm of goalkeeper Fawzi Chaouchi.
Slovenia typically is stronger against other Eastern European nations. It's less comfortable with northern European teams which, like the U.S., often play a more physical game.
Asked by a Slovene reporter whether that would be a concern on Friday, Kek got irritated and refused to answer.
Slovenia is injury-free, with all 23 players available for Friday's match at Ellis Park in Johannesburg.
U.S. goalkeeper Tim Howard was injured in the first half against England when Emile Heskey's boot struck him in the ribs below the breastbone. But Howard said he'll be ready to face Slovenia, even if it means getting injections of painkillers.
"It's probably going to be more of a tactical battle and a bit of a chess match," Howard said of the Slovenia match. "Is there still another group game? Sure. But I think we've got to go all out and try to get this result.
"And if we end up getting the draw, OK. Then we can worry about the last game. But I think it's a game that we need to win."
