By GREG BEACHAM
AP Sports Writer
LONDON (AP) - The British boxers already know they're making a big medal haul out of their home Olympics.
Errol Spence is the only one who can prevent the American men from leaving London empty-handed.
Spence must beat Russia's Andrey Zamkovoy to avoid the first medal shutout of the U.S. men's boxing team in Olympic history when they meet Tuesday night in a quarterfinal welterweight bout.
Spence thought he was out of the Olympics for a few hours after he fought India's Krishan Vikas last week, but amateur boxing's governing body overturned the result on an accumulation of uncalled holding fouls. The Americans have won easily the most boxing medals in Olympic history, but their two-decade decline could culminate in a blanking unless Spence comes through.
And though the British boxers must wait a few days to add their medals to the home team's enormous Olympic haul, they're lining up for big weekend bouts and even bigger celebrations.
Middleweight Anthony Ogogo and super heavyweight Anthony Joshua both clinched medals in quarterfinal bouts Monday night, guaranteeing Britain will win at least four Olympic medals in front of its frenzied home fans.
Flyweight Andrey Selby and welterweight Freddie Evans could join them Tuesday night with victories. Selby faces Cuba's Robeisy Ramirez, and Evans will try to stop Custio Clayton from securing Canada's first Olympic boxing medal since 1996.
Ogogo jumped ahead early in a 15-10 victory over Germany's Stefan Haertel, and Joshua knocked down China's Zhang Zhilei during a 15-11 win in the session's final bout. Although two of the three British women lost their quarterfinals earlier in the day, flyweight Nicola Adams also earned a medal _ and captain Tom Stalker could clinch his own medal Wednesday.
Ogogo isn't surprised by the British dominance in the amateur sport, which has its roots in Amir Khan's silver medal as the only fighter in Athens eight years ago. After the British brought home three medals from Beijing, they'll have even more in London.
"We've got the best coaches in the world," Ogogo said. "We've got the best team in the world, in my eyes."
When the fans weren't singing and making up cheers for their new pugilistic stars, they watched lightweight Vasyl Lomachenko of Ukraine clinch his second Olympic boxing medal with a 14-9 victory over Puerto Rico's Felix Verdejo on Monday night. Later, middleweight Vijender Singh was eliminated in the biggest blow yet to the beleaguered Indian team.
Evaldas Petrauskas also secured Lithuania's first-ever Olympic boxing medal, beating Italy's Domenico Valentino in a 16-14 upset. Valentino's teammate, defending gold medalist Roberto Cammarelle, barely survived his quarterfinal super heavyweight bout, edging Morocco's Mohammed Arjaoui 12-11.
The dynamic Lomachenko was tested in his quarterfinal bout with Verdejo, who constantly moved forward to challenge the two-time world champion. Verdejo's aggression forced Lomachenko to show off his defense, reflexes and stunning footwork, and it all added up to another comfortable win for the Beijing Olympics' best boxer.
Verdejo still scored more points than Lomachenko allowed in any of his five dominant victories in Beijing, although the amateur scoring system has since been altered in ways that encourage higher scores.
"I fought a good fight against a top-notch fighter," Verdejo said. "I hope this experience will help me grow as a fighter."
Lomachenko earned a tough semifinal bout against Cuba's dynamic Yasnier Toledo, who beat Kazakhstan's Gani Zhailauov 19-11.
But the Indian team had another night to forget.
Singh's 17-13 loss to Uzbekistan's Abbos Atoev cast a pall over ExCel arena, where hundreds of Indian fans had hoped the Beijing medalist could rescue their sinking team.
Singh became a national icon four years ago by winning bronze, India's first medal in Olympic boxing. India's amateur boxing culture expanded rapidly after Beijing, and seven men qualified for London along with flyweight Mary Kom, who secured a medal with a quarterfinal victory earlier Monday.
But the Indian men have been hit by constant misfortune in this tournament, from a handful of close decisions to AIBA's reversal of Vikas' ugly win over spence. Only light flyweight Devendro Laishram is still alive on the men's side.
Singh didn't dominate Atoev, but couldn't get the decision against a fighter he shut out at the Asian Games two years ago. Singh rushed to the locker room, but assistant coach Blas Iglesias shouted: "It's a mafia! It's a mafia!"
Ogogo got off to a strong start against Haertel, who injured his hand in the first round and couldn't fight with his usual aggression. Ogogo held on to the decision despite Haertel's strong third round.