The United States were “ice cold” and produced “the worst shooting performance we’ve seen” but claimed a 85-73 win over Montenegro in their huge World Cup clash on Friday night.

The World No. 2 ranked US side stacked with NBA talent came into the second-round group game with a perfect 3-0 record and a huge favourite to win gold.

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Montenegro, a lowly 18th in the FIBA rankings coming into the tournament, reached the second round with a 2-1 record, beating Mexico and Egypt before a heavy loss to Lithuania.

All of that was thrown out the window in a physical first half in Manila.

The European side, which is led by Chicago Bull Nikola Vucevic, took the fight right up to the Americans.

That included an elbow thrown by Montenegro’s Marko Simonovic into the stomach of US big man Walker Kessler late in the first half.

Simonovic was hit with an unsportsmanlike foul before the underdogs were also hit with a tech foul as the wheels threatened to fall off their hot start.

“An unsportsmanlike foul has been called on Simonovic,” FIBA commentator Jeff Taylor said during the game. “Completely uneccessary.

“And now there’s a technical foul as well and all of a sudden, the USA’s toughest challenge of this World Cup has gone off the rails completely.

“Montenegro with a lack of emotional discipline. Simonovic just swung his right elbow into his side.

“I don’t think you should ever throw an elbow. There’s too big a risk.”

Instead of it rattling the Montenegrins, however, they finished the half strong and took a shock 38-37 lead into the main break.

It led to US assistant coach Mark Few to yell “let’s get some fire in our eyes” during the halftime break.

The second round is not a knockout round at the World Cup, with teams moved into new groups, where the top two progress to the quarter-finals.

Part of the issue for the Americans was some horrid shooting from the floor in that first half.

That included hitting just one of their nine three-point attempts in an effort that should give the rest of the teams in the tournament some hope.

“Wow. USA overall are shooting well from the line, but shooting below 50% inside the arc and shooting 35% overall,” Taylor said.

“Very un-USA-like.

“This is the worst shooting performance from the USA that we’ve seen so far in this tournament. Ice cold 35% from the floor.

“Unexpected I think from most people, Montenegro leading at halftime 38-37 over the USA in the opening game of the second round for both teams.

“Montenegro will be in the locker room talking about the great opportunity they’ve got to spring an upset and get probably the biggest win in their history.”

The European side kept up the pressure early in the second half, stretching the lead to five points in the early exchanges.

But the Americans gradually fought their way on top, with some vastly improved shooting helping them to a 24-17 third quarter for a five-point edge at the last break.

Montenegro kept fighting, but the US were too composed down the stretch as they avoided the huge upset, 85-73.

“A real battle won by the USA today. It was not easy at all,” Taylor said in closing.

“Montenegro, when they look back at this, maybe a couple of shots away at key parts of the game from this one being different.

“This was an awkward game for the USA.

“I wonder what other teams may have learned from this.”