By Ridge Mahoney

The U.S. women's team has played 20 games this year without being beaten, yet none of those games has greater importance than the Gold Cup semifinal against Mexico Wednesday at Home Depot Center (Fox Soccer Channel, 10 pm ET).

By winning, the USA clinches a spot in the 2007 FIFA Women's World Cup next September, regardless of what it does in Sunday's gold-medal game. And while a win over Mexico, which the U.S. beat two months ago, 3-1, in Rochester, is all but a foregone conclusion, U.S. coach Greg Ryan expects his players to come out aggressively and leave nothing to chance.

Two years ago, the teams met in the final game of the 2004 CONCACAF Olympic qualifying tournament, and the Americans fell behind, 2-0, before rallying to win, 3-2.

"There is added pressure because there is one game and you're in," says Ryan, who would prefer group play to be used for World Cup qualifying as is done in most of the world. "Now, if you lose a game, you still have a shot to qualify by winning your next game and then you're playing against Japan. But there is additional pressure with just a one-game situation.

"It's a funny game. We've all seen games where a team dominates but still loses. That's just the way it is sometimes in soccer, much more so than in other sports."

In the other semifinal, Canada plays Jamaica (FSC, 7:30 p.m. ET). The two semi winners automatically qualify, the losers meet in a third-place match Sunday, and the winner of that game advances to a two-game playoff with Japan.

Abby Wambach, playing in her hometown, scored two of the goals in the 2004 win over Mexico. She's been hobbled by a sprained ankle suffered in the Peace Queen Cup earlier this month, and didn't play in the tournament final, which the Americans won by beating Canada, 1-0, on Kristine Lilly's 116th international goal.

"We played our same style, our same system, we just inserted Natasha Kai," says Ryan. "We played very well. Obviously, we're not quite the same team without Abby because she's been so good for us, but I think we'll probably put Tash in there and go after it like we did in the final of the Peace Cup."

The U.S. has won all 17 meetings with Mexico and can set a team record for longest unbeaten run.

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BY THE NUMBERS
30 The USA's 30-game unbeaten streak, which began with a 5-0 victory over Mexico Dec. 8, 2004, in the final match for Mia Hamm, Julie Foudy and Joy Fawcett, matches the longest unbeaten streak in U.S. women's history.
29 Since Greg Ryan took over as coach in 2005, the USA is undefeated in 29 games (24-0-5).
17 The USA has beaten Mexico all 17 times they have met. In their most recent game, the Americans won, 3-1, on Sept. 13 in Rochester, N.Y.
14 The USA has all 14 games it has played in Women's World Cup qualifying,
12 The USA crushed Mexico, 12-0, in 1991 in the first qualifier it ever played. It has opened against Mexico in every qualifying tournament, also winning, 9-0, in 1994 and 3-0, in 2002.

ROSTERS
USA
Goalkeepers: Briana Scurry (U.S. residency), Hope Solo (U.S. residency); Defenders: Lori Chalupny (U.S. residency), Tina Frimpong (U.S. residency), Stephanie Lopez (Univ. of Portland), Kate Markgraf (U.S. residency), Heather Mitts (U.S. residency), Christine Rampone (U.S. residency), Cat Whitehill (U.S. residency); Midfielders: Angela Hucles (U.S. residency), Carli Lloyd (U.S. residency), Marci Miller (U.S. residency), Leslie Osborne (U.S. residency), Aly Wagner (U.S. residency); Fowards: Danesha Adams (UCLA), Natasha Kai (U.S. residency), Kristine Lilly (U.S. residency), Heather O'Reilly (Univ. of North Carolina), Lindsay Tarpley (U.S. residency), Abby Wambach (U.S. residency).

MEXICO
Goalkeepers: Jennifer Molina (New England Mutiny/USA), Sophia Perez (San Diego Gauchos/USA), Pamela Tajonar (FC Indiana/USA); Defenders: Marichuy Castillo (Mexico FC), Liza Gomez (Mexico FC), Lulu Gordillo (Andrea's Soccer), Marlene Sandoval (Mexico FC), Chayito Saucedo (Mexico FC), Isabel Valdez (Mexico FC); Midfielders: Monica Gonzalez (California Storm/USA), Fatima Leyva (Mexico FC), Juana Lopez (Mexico FC), Paty Perez (Mexico FC), Monica Vergara (Mexico FC); Fowards: Charlyn Corral (FC Indiana/USA), Maribel Domi­nguez (Levante/SPA), Iris Mora (no club), Monica Ocampo (Gacelas Univac), Carmenita Padilla (Univ. of the Pacific/USA), Guadalupe Worbis (FC Indiana/USA).