SANTO DOMINGO, Dominican Republic -- Pan American Games gold eluded the United States in two team sports Wednesday night, with a trip to the Olympics also slipping away in field hockey.

In most cases, a field hockey silver medal at an international competition brings huge satisfaction to Americans. Not this time, as a 3-1 loss to powerful Argentina in the final meant the United States must find another route to the Athens Olympics.

The volleyball team lost to Cuba in the men's semifinals, a five-set thriller in which the Cubans rallied for victory as the Americans tired. Brook Billings of Santa Barbara, Calif., scored 20 points on 18 kills and two blocks in the 22-25, 25-19, 17-25, 25-23, 15-8 defeat.

But the swimmers kept right on filling the medals podium. The women's 400-meter freestyle relay squad set a games record of 3 minutes, 41.93 seconds, a nearly five-second edge over runner-up Canada. Amanda Weir of Lawrenceville, Ga., led off the relay with the fourth-fastest time by an American (54.46), followed by Christina Swindle of Miami; Colleen Lanne of Tucson, Ariz.; and Courtney Shealy of Columbia, S.C.

In a 1-2 finish, Elizabeth Hill of Atlanta set a games record of 4:10.18 in the 400-meter freestyle, with Morgan Hentzen of La Habra Heights, Calif, taking second. Then Diana MacManus of Irvine, Calif., won the 100 backstroke, just ahead of Shealy.

Argentina's Jose Meolans won the men's 100 freestyle, and Brazil's Rogerio Romero edged Luke Wagner of Englewood, Colo., and Joey Faltraco, Union Mills, N.C., in the 200 backstroke.

On a busy day for U.S. teams, the women's softball world champions gave up their first run of the tournament, but beat the Dominican Republic 2-1. Crystl Bustos reached third on an error in center field when her towering fly ball was dropped. Stacey Nuveman singled her home in the seventh inning.

Jennie Finch fanned 15 for the Americans, who are in the final and will await the winner of the Canada-Dominican Republic elimination game Thursday.

The U.S. men lost 3-2 to Canada. The Canadians made the final, and the Americans can get there if they beat Argentina on Thursday afternoon.

The Americans lead the medals count with an even 200: 85 golds, 62 silvers, 53 bronzes. Cuba is next with 124: 58-31-35.

Featherweight Aaron Garcia of Vista, Calif., scored the United States' biggest boxing win thus far, beating Cuba's Yosvani Aguilera, 16-14.

"It was a hard bout,'' Garcia said. "I liked the style he boxed, he fit my style well. He's more of a boxer.

"I kept up the pressure. Coach kept telling me to throw more punches and work the body, and it worked well.''

The women hockey players got the first shot at a big win. But Agustina Garcia scored two goals and Argentina earned the berth in the 2004 Olympics. The Americans must now try to qualify in a tournament in New Zealand in March.

"They came out flat and we could have jumped on them in the first 15 minutes,'' goalie Peggy Storrar said. "But we had some nerves. That was our opportunity, but we didn't do it.''

Still, it was a positive experience for the Americans, who hardly have been a force in the sport. And there remains that shot at Athens.

"It's never fun to lose,"said U.S. coach Beth Anders. "Argentina is a very good team. We're definitely growing as a team. That's a positive.''

The United States had a positive result in cycling as Tanya Lindenmuth of Trexlertown, Pa., won the keirin cycling race. Chris Witty of Milwaukee, a gold medalist at the 2002 Olympics in speed skating, finished second in the women's sprint to Nanci Contreras of Mexico.

Another U.S. gold went to Tim Thackrey of Tarzana, Calif., who defeated Oscar Salazar of Mexico, 2-1 in the flyweight taekwondo division.

"I knew in the end that I had it,'' said Thackrey, whose parents traveled to Santo Domingo for the fight. "This is easily the biggest win of my career. I've put a lot of things on hold to chase this dream, and I can't believe that I actually did it. I came here to win gold and to keep moving towards the Olympics in Athens next year, so this win is huge.''

The Americans came away empty in three weightlifting classes. Carrie Boudreau of South Portland, Maine, who scheduled her chemotherapy treatments for breast cancer around the games, finished seventh in the 58-kilogram class.

"I lifted about 90 percent of what my max is,'' Boudreau said. "I feel great. This was a fun competition for me.''