But unless welterweight Errol Spence Jr., whose loss to an Indian rival was reversed, can beat Russia’s Andrey Zamkovoy on Tuesday the US males will leave without a medal for the first time since the amateur version of the “sweet science” was introduced 108 years ago.

That would be a humiliating showing for a once-robust program that has been reduced to Third World status in the international standings, winning a sole bronze at the 2008 Games in Beijing and also at last year’s world championships in Azerbaijan.

“We need some medals,” acknowledged head coach Basheer Abdullah, the 2004 mentor who was brought back this spring after Joe Zanders stepped down and longtime British coach Terry Edwards reportedly turned down the job. “Americans support winners. Once we develop some winners in our sport again I think the American people will grab onto that and start supporting us a little bit more.”

During the past dozen years, though, boxing has fallen off the radar screen in the States as the sport has become less popular and the golden flow has vanished. Four decades ago, when Howard Cosell was ringside for ABC and the US-Cuba rivalry was at its zenith, boxing was a prime-time attraction. The 1976 team, which included Leonard and the Spinks brothers, won seven medals in 11 weight classes, five of them gold. As late as 1988 the Americans still collected eight. At the last three Games, though, they’ve earned a combined seven, only one of them gold.

This time, though, the US has hit rock-bottom with most of its entrants saying goodbye 10 minutes after they were introduced. Five of them — former world flyweight titlist Rau’shee Warren, light welterweight Jamel Herring, light heavyweight Marcus Browne, heavyweight Michael Hunter II, and super heavy Dominic Breazeale — lost their first bout. Three others — bantamweight Joseph Diaz Jr., lightweight Jose Ramirez, middleweight Terrell Gausha — were eliminated in their second outing.

If the competition jury hadn’t reinstated Spence after ruling that opponent Krishan Vikas should have had four points deducted for warnings, the American roster would have been wiped out before the quarterfinals.

Reasons for the medal drought abound. The breakup of the Soviet Union, which added 14 new countries to the mix. The rise of the Asian nations. The introduction of a new scoring system. A domestic federation riddled with infighting and cronyism. The lack of continuity from Games to Games with a changing cast of officials and coaches.

“Last time it was difficult,” said Warren, the first US fighter to compete in three Games. “We had to move away from our families for a year [to Colorado Springs] to get ready. The coaches that they had besides the head coach were inexperienced. They couldn’t tell me what to do. I was telling them. The only thing good about it was plyometrics.”

Yet the lead-up to these Games was far more arduous and fractious. Since only three boxers — Warren, Diaz, and Spence — qualified from the world championships, USA Boxing decided to hold another set of Olympic trials during the winter at which four on the original roster failed to make the team. Then, the seven unqualified fighters had to go to Rio de Janeiro in May for a second-chance tournament.

Meanwhile there was turmoil at the top. President Hal Adonis was removed by the executive board at the end of May in the wake of a New Yorker story in which he was quoted as saying that “half of our girls have been molested and half of our girls are gay” and that he asks would-be boxers who call him if they’d ever been hit by their parents: “If they say no I say, I don’t think you belong in boxing.” And it didn’t help that Abdullah was brought back without the federation realizing that he couldn’t work the corner because he’d trained professionals.

Still the team arrived here in its customary optimistic mood after qualifying nine entrants, more than any other country. “Now we have some excitement going,” said USA Boxing executive director Anthony Bartkowski. “We have the power of numbers coming.”