MANAUS, Brazil—Two soccer teams. Two press conferences. Two very different atmospheres.

Yesterday both Paolo Bento of Portugal and United States national team coach Jurgen Klinsmann addressed the media ahead of their crucial Group G showdown (6 p.m. ET; ESPN), but judging from the tone it was hard to tell which coach helmed the No. 4-ranked team on the planet and which was in charge of the upstart from North America."

"I know we are in a difficult situation," Bento said in an interview that was by turns both conciliatory and defiant. "I've been in this sitation before. In difficult moments, I always say, we get to know ourselves better."

With four starters out of action; a fifth, veteran defender Bruno Alves, in doubt; and his superstar, Cristiano Ronaldo, recovering from a knee injury, Portugal is reeling. And desperate.

Bento summed up the situation in succinct fashion: "Either we win, or we start packing our suitcase."

Klinsmann, on the other hand, came out swinging.

“This is now the moment where you can prove yourself,” he said. “This is now the moment that you can step up and play those guys and put them in place. We want to put Cristiano and his team in place.”

With yesterday's Group G result, a rousing 2-2 tie between Ghana and Germany, the U.S. has a much better sense of its World Cup situation. Amid all of the scenarios, one thing is certain: a win against Portugal today guarantees the Americans will reach the knockout round of the tournament—an oft-stated team goal.

READ ASN'S DEEP-DIVE TACTICAL ANALYSIS

As U.S. goalkeeper Tim Howard put it, "This is a massive game. A turning point for us. If we win, we've taken care of business."

Klinsmann seemed very encouraged by Ghana's strong showing against the powerful German squad.

“It just confirms what we all knew in the beginning: that it’s a very difficult group,” he said. “A draw between [Ghana and Germany] just shows that, but also it puts the positive result that we made against Ghana in the right perspective. For us, it’s a huge opportunity for us here tomorrow in Manaus.

"We’ll definitely go for it.”

With Jozy Altidore out with a hamstring injury, the biggest question hanging over the U.S. national team will be at the striker position. Will Klinsmann push Clint Dempsey, who is nursing a broken nose suffered in the Ghana match, up top? If so, will Dempsey be paired with Aron Johannsson? Chris Wondolowski? Neither?

It's certainly not an ideal situation for the Americans, but Portugal is in a far worse crisis. It will be without three of its four starting defenders and its first-choice goalkeeper.

CLICK: HOW SHOULD THE U.S. ATTACK PORTUGAL?

In another words, U.S. attackers will be staring down a lineup comprised of second stringers. Klinsmann, a striker during his playing days, seemed more eager than ususal to get to it.

“We want to take our game to Portugal. We want to get three points tomorrow,” he said. “We want to qualify for the next stage. We are full of energy. We are very impatient.

"We can’t wait to get this thing started.”

John Godfrey is the founder and editor in chief of American Soccer Now.