By Steve Keating

RIO DE JANEIRO (Reuters) - The United States men's basketball team continued to steamroll toward a third straight Olympic gold medal as they thumped Venezuela 113-69 on Monday, adding a bit of sporting misery to the recession-ravaged country.

An upset victory over the U.S. would have done nothing to improve conditions in Venezuela, where food and medicine are running scarce and annual inflation is in triple digits, but it certainly would have lifted the nation's spirits.

The game marked the first time the U.S. and Venezuela, at number 22 the second-lowest ranked nation in the tournament, had ever met on the Olympic stage and the South American underdogs were at least able to walk off court with heads held high having battled their opponents to an 18-18 draw in the opening quarter.

But there was no panic from the U.S. who eventually showed their class while extending their Games' winning streak to 19-0, a run of domination that dates back to the bronze medal game of the 2004 Athens Olympics.

"Trying to defend these great players, it is impossible to keep the intensity the whole game," explained Venezuela coach Nestor Garcia. "We try not to give them a chance to run because when they run they kill.

"We believe we play with heart and pride against these people. We play the same against everybody, we don't care if it's the 'Dream Team' or Serbia, we try to be intense because we know the talent these teams have is great.

"If we don't leave it all on the court, we don't have any chance."

Venezuela were back in the Olympics for the first time since 1992 and they were given no chance of pulling off an historic upset as they headed into Monday's game.

For a very brief moment a whiff of an upset actually hung in the air at the Carioca Arena as Venezuela refused to surrender, matching their mighty opponents basket-for-basket going into the second quarter.

Then suddenly the United States shifted into another gear and left the Venezuelans in their dust, going on a 20-6 run to end the half and seize control of the contest.

"We weren't worried, we just had to make some adjustments," said U.S. captain Carmelo Anthony, when asked about the opening quarter. "We missed some shots early, played their game, but once we made those adjustments we were ok."

Next up for the U.S. are 11th-ranked Australia (2-0), who earlier on Monday eased past Serbia 95-80.

"It is going to be a grind-out game, I'm looking forward to it," said American Kevin Durant. "Most of their main players play in our league (the National Basketball Association) but we'll prepare for them tomorrow and see what we got."

(Editing by Mark Lamport-Stokes)