Kerri Walsh Jennings will not get her fourth straight beach volleyball gold

For all of the troubles during the first week and a half of the Summer Olympics, the stadium-shaking potential of the enterprise pounded through the beach volleyball venue on the Copacabana shore in the early hours of Wednesday.

Members of the sellout crowd chanted “monster block” and waved their arms in unison while strobe lights flashed each time Brazil’s duo of Agatha and Barbara knocked down the ball.

Boos and catcalls drowned out thumping music during every serve by the U.S.’ Kerri Walsh Jennings and April Ross.

And each Brazil point unleashed such a wave of delirium among the masses clad in the country’s yellow and green that the temporary structure wobbled back and forth.

As waves crashed nearby, Agatha and Barbara, the reigning world champions, defeated Walsh Jennings and Ross, 22-20, 21-18, to advance to the gold-medal game.

“They outplayed us in pretty much every way,” said Walsh Jennings, who had never lost a match at the Olympics before.

The loss ends her bid to win a fourth consecutive gold medal at the Games. She previously teamed with Misty May-Treanor, who retired in 2013, for those medals. Ross replaced her.

The Americans, the world’s No. 3 in the latest FIVB rankings, will play Brazil’s Larissa and Tulita — the players, like the country’s soccer icons, use only one name — later Wednesday in the bronze-medal match.

Agatha and Barbara entered the competition as the world’s 20th-ranked team. They face Germany’s Laura Ludwig and Kira Walkenhorst for the gold medal Wednesday. The Germans upset Larissa and Talita, the top-seeded team at the Games, on Tuesday to advance.

Walsh Jennings and Ross never looked comfortable against the Brazilian duo, as the crowd sang in unison to techno songs and dancers entertained with brief routines during breaks in the atmosphere that resembled a raucous party as much as a volleyball match.

But the enthusiastic crowd — the Americans insisted it didn’t affect their play — didn’t relent from Brazil’s first point. Fans waved scores of Brazilian flags. They erupted each time Agatha or Barbara drilled the ball off the U.S. players’ hands.

“We had so many chances to take the match into our hands and do what we wanted, but we didn’t do that,” Ross said. “They were just sharper.”

In five previous games at the Olympics, the Amer-icans had lost just one set. That came at the end of pool play. But the same precision wasn’t on display Wednesday.

Everyone in the stadium stood as the final point approached.

The wobble in the stands turned into a vigorous swaying as fans jumped up and down.

The final shot bounced off Ross’ hands. The game ended.

The crowd’s game-long roar grew louder. As the smell of fried food and beer drifted across the beach from nearby eateries, the real party began.

nathan.fenno@latimes.com

Twitter: @nathanfenno

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