Ronaldo, who has been playing despite a left-knee injury, sent in a cross in the fifth minute of stoppage time and Varela scored with a diving header in the last seconds of the match.
"Obviously when they get it in in the last second, it is unfortunate, but I think it was an amazing game, an amazing performance by all our guys," he said. "We just go in it the tougher way, so we gotta go and beat Germany, get a result against Germany, that's what we gotta do."
Klinsmann's reveled in the American's underdog status, saying the pre-tournament favourites to move on from the group stage -- Germany and Portugal -- have been given every advantage in the World Cup.
"They played yesterday, we played today. We played in the Amazon, they played in a location where they don't have to travel much," he said. "Everything was done for the big favourites. We're going to do it the tough way."
Now, if the United States and Germany draw on Thursday, both will advance to the knockout stage regardless of Ghana and Portugal's result.
"I don't think that we are made for draws, except for what happened tonight," Klinsmann said of Thursday's match against Germany. "Both teams are going into this game and they want to win this group. We want to be in the drivers' seat for round of 16, that is our goal. We would be through already, which people didn't expect before this. There's a lot more respect coming from our opponents."
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- Group G qualifying scenarios
- Germany vs. United States, Thursday, 12 p.m. ET, ESPN
There have already been questions about how much attacking will occur in that match, as there's precedent for German involvement in a mutually-assured advancement situation.
In 1982, West Germany was in a group with Algeria, Austria and Chile. A 3-2 Algeria win in their last match meant Algeria would be the first team to reach the knockout stage unless West Germany beat Austria by one or two goals -- in which case both European sides would advance. After Germany's Horst Hrubesch put the Germans in front in the 10th minute, both teams realised they were through if results held and basically stopped playing for the final 80 minutes.
The incident is what prompted FIFA to change the format of the final match of the group stage. All four teams in a group now play their third match simultaneously to avoid this scenario.
"There's no such call," Klinsmann said of any potential accord between the U.S. and German coaches. "My job is to get everything done in order to have us go through to the round of 16. There is no time to have friendship calls. It's all about business now.
"Everybody's growing into this tournament. You want to start well and we got the Ghana game into our legs. We build with every moment. Every game you play is getting bigger and you see these things coming through.
"We're going to take our game to Germany and give it a real fight. We are capable of surprising even more teams in this tournament," he said.
There is an incentive for the U.S. to try to win the game. The Americans will need a win to finish first in the group, which would likely allow them to avoid Belgium in the next round in favour of a weaker opponent -- Algeria, Russia or South Korea. A draw will be enough for Germany to finish top.
Man of the match, U.S. goalkeeper Tim Howard, singled out the work of his teammates after Sunday's draw.
"Realistically, we've given ourselves every chance to advance. We are where we want to be right now," he said. ""We harped over and over again for Kyle [Beckerman], Michael [Bradley] and Jermaine [Jones[ to be the engine. My hat goes off to them. They have a tireless work ethic and we'll never lose that.
"Football is cruel sometimes. It ebbs and flows," he said. "We'll try to give ourselves 12 hours or so to ponder the result. We have a good chance to go through and we're excited."
The last-second draw denied the Americans a spot in the second round, but it kept Portugal alive in the tournament.
"We like to do things the tough way. It's the American way," Matt Besler. "Everyone can be proud of where we're at right now. As players, were laying everything out on the line. That's all you can ask for. We're disappointed not to have six points. We could taste it with minutes left, but we're still in control of our own destiny."
Sympathy for Klinsmann
The ESPN FC World Cup Encore cast discuss Jurgen Klinsmann's comments regarding their draw with Portugal favouring Germany.
Klinsmann: It's all about Germany now
United States head coach Jurgen Klinsmann insists that his team will be focused on Germany and will be moving on from their draw with Portugal.