The week that started so disastrously for the U.S. baseball team at the Pan American Games is turning out rather well. The United States beat Panama tonight, 5-2, at CanWest Global Stadium to advance to the semifinals against Mexico and needs only one more victory to secure a berth in the 2000 Olympics.

The Americans will face Mexico on Sunday night, after Cuba and Canada meet in Sunday's first semifinal. The Canadians, the only undefeated team in the tournament, beat Cuba, 8-1, on Thursday.

"We came here to win the gold medal," U.S. Manager Buddy Bell said. "We have to beat Mexico to do that. We've got to be ready to play them. As far as we're concerned, we still have to win two more games."

But the semifinals are the pivotal games, because only the top two finishers of the Pan Am tournament will qualify for Sydney. The gold medal game is Monday.

Cuba eliminated the Dominican Republic with a 3-1 win in the day's first quarterfinal. Canada beat Guatemala, 12-2, in a game that was shortened to seven innings because of the 10-run mercy rule. And Mexico upset Nicaragua, 5-1.

The United States began the tournament with a mistake-filled, extra-inning loss to Canada on Monday. Since then, the U.S. team has won four straight, including a victory over Cuba, winners of the past seven Pan Am Games.

U.S. pitcher John Patterson--the starting pitcher from Monday's loss--dominated Panama, retiring the first 11 batters. In eight innings, he gave up two hits, struck out seven, and did not walk a batter. Todd Williams pitched the ninth for the United States.

The United States scored four runs on five hits in the third inning. Second baseman Adam Kennedy drove in Dave Roberts with a double to right. The next batter, Jason Hardke, singled to left, but Panama's Joel Vega overran the ball, allowing Kennedy to score.

After Craig Paquette flied out to left and Milton Bradley walked, Jon Zuber followed with a two-run double to center.

Paquette hit his second home run of the tournament in the fifth--a leadoff home run to left field--to increase the U.S. lead to 5-0.

Patterson, a Class AA pitcher in the Arizona Diamondbacks' organization, did not allow a hit through 5 2/3 innings but ran into trouble when he fielded a bunt by Earl Agnoly, bobbled the ball, and then threw too late to first base.

Patterson, who was visibly upset with himself for the mistake, was given an error on the play, preserving his no-hitter. But the next batter, Audes DeLeon, broke up the no-hitter and shutout bid with a two-run home run to right field.

"I focused on the game, but I knew I had a no-hitter going," Patterson said. "Every time I looked up to see how many outs there were, the zeroes were there, looking at me in the face. If I could've fielded that ball, who knows?"

Now the U.S. team gets to face Mexico (2-3), the team it beat, 5-1, on Tuesday. Left-hander Mark Mulder will make his second start against the Mexicans; on Tuesday, he gave up one run on six hits in 6 2/3 innings.

"The loss to Canada is not in our minds," said Patterson. "If you dwell on things in the past, you're not thinking about the present. We're thinking about Mexico now. If it ends up that Canada is in the finals, well, that's when we'll think about Canada again."