RIO DE JANEIRO >> A towel draped over his left shoulder, Erik Shoji sat on the bench alongside big brother Kawika and pondered what might be going so wrong for the young United States team in its Olympic volleyball opener against hard-hitting Canada.

For a group of largely Olympic first-timers determined to show that youth and inexperience don’t necessarily mean anything on the biggest stage, the fifth-ranked Americans looked at times sloppy and out of sorts in falling 25-23, 25-17, 25-23 to No. 12 Canada on Sunday in the first pool match for both countries.

“We knew we were the underdog in this pool and this match,” Canada captain Frederic Winters said. “It’s the Olympic Games and our team was highly motivated and it showed on the court today.”

From serves into the net early and others that sailed long, to kill attempts that fell wide and missed blocks, the Americans were off from the start. And Canada capitalized.

Later Sunday, defending champion Russia won in four sets against a Cuba team that had to revamp its roster in the past month because six players are being held in Helsinki on suspicion of aggravated rape, according to Finnish police.

Argentina beat Olympic first-timer Iran in three sets in the late match.

The U.S. will now look to regroup to face Italy on Tuesday.

“Hopefully we all fight back for the next match,” Erik said. “There’s always jitters in the first match.”

The Canadians also beat the U.S. in a five-setter for the Champions Cup title in May 2015 before the Americans won on the way to last year’s World Cup crown in Japan.

“It was an unfortunate way to start the tournament,” said U.S. captain and third-time Olympian David Lee. “We didn’t find a level of consistency that we could sustain throughout the match.”

U.S. coach John Speraw committed to a youth movement, and that means most of the Americans lack Olympic experience — though they receive plenty of insight from four-time Olympic teammate Reid Priddy, third-timer Lee and Matt Anderson in his second games.

Lee expects everybody to respond, learn from this and adjust in a hurry.

“I hope so, and I believe so. These guys have proven themselves on the biggest stages,” he said. “That’s very uncharacteristic for some of the young players to make some of the errors they did at some of the moments they did. I expect them to be extremely motivated in the matches to come.”

Despite the disappointing first result, the Shojis are enjoying their time together in Rio de Janeiro as first-time Olympians — with a supporting cast of about a dozen that came along to cheer their special accomplishment.

Including their decorated coaching dad, Dave, the longtime head of the University of Hawaii program.

The Shojis, who played for Stanford, and setter Micah Christenson all are from Hawaii and they are three of eight U.S. players making their Olympic debuts. With lights flashing from all angles, Erik offered a wave to a section of U.S. supporters as the Americans entered for pregame warmups.

The brothers cherish the chance to be there for each other on the biggest stage.

“We’re basically best friends and it’s just a really neat thing to go through the experience with him,” Kawika said. “We’re really close. We might be going through different things off the court but then when we come here we’re going through it together. We can basically read each other’s minds.”

Earlier Sunday, Brazil’s Bruno Rezende, Mauricio Souza and William Arjona were among the last to leave the court as many of the players thanked the fans with photos, handshakes, smiles and thumbs-up signs.

The host Brazilians beat Mexico 23-25, 25-19, 25-14, 25-18 and Lucas Saatkamp’s winning kill sent the crowd into a frenzy as players threw their arms up in celebration.

Egypt’s Ahmed El Kotb was carried off the court by teammates and athletic trainers worked on his right ankle on sideline during the first set of a loss to Poland.