Four days after being routed by a superior Argentina squad in their Copa America opener, the Americans were humbled even further tonight in a 3-1 loss to Paraguay that put them on the brink of elimination.

Ricardo Clark's goal in the 40th minute had tied the score 10 minutes after Edgar Barreto had put Paraguay ahead.

But then, Jimmy Conrad all but conceded Oscar Cardozo's goal in the 56th minute, which gave Paraguay a 2-1 lead. Salvador Cabanas scored his third goal of the tournament in injury time after the Americans blew chance after chance offensively.

Clark's first international goal in nine appearances was little consolation for the Americans, who lost their second straight after going 10-0-1 to start the year. It also was their first loss to Paraguay in five games and all but eliminated the U.S. team from South America's championship.

The 13th-ranked United States (0-2) would have to rout No. 31 Colombia in the final group stage game and get lots of help from other teams. Paraguay, ranked 37th, joined Mexico in the quarterfinals. The United States and Mexico are invited guests.

After winning the Gold Cup with players like Landon Donovan, DaMarcus Beasley and Carlos Bocanegra, U.S. coach Bob Bradley brought a largely young and untested squad to Copa America.

Did the inexperience show.

After falling apart against Argentina in the second half, the Americans were sloppy from the start against Paraguay. The U.S. had a 14-12 advantage in shots, but Eddie Johnson, Justin Mapp, and Drew Moor all missed great chances in the last 15 minutes. Moor became third player in the tournament to make his U.S. national team debut.

The Americans gave up a sloppy goal to Barreto in the 30th minute when he outran Conrad and Sacha Kljestan for a through ball. He connected with a beautiful sliding kick to beat Kasey Keller, who had come out of the box.

But Clark rallied the Americans 10 minutes later. Taylor Twellman knocked down a deep ball and one-touched it to Clark, who buried a hard, right-footed shot just inside the near post from just inside the penalty area.

Paraguay goalkeeper Justo Villar left in the 56th minute after apparently injuring his right leg. But what should have been an advantage for the Americans quickly turned into a fiasco.

Backup Aldo Bobadilla had barely gotten to the goal when, at the other end, Jonathan Bornstein was trying to clear the ball back to Keller. Conrad, who started against Ghana at last summer's World Cup, let the slow-rolling ball go by, and Cardozo sprinted in to intercept it.

With Keller frozen, Cardozo slotted a left-footed shot into the net to put Paraguay up 2-1.