He's flown around the world to watch games, breaking down several years of videos for telling details. And he's sent assistants Billy McNicol and Phil Wheddon on reconnaissance missions, too.

He'll need all that insight when the favored United States opens Tuesday in the women's World Cup against Asia's best team.

"I think North Korea is one of the top three or four teams in the tournament and the most mobile team in the tournament," Ryan said. "They can run from six-yard box to six-yard box more times and faster than any team in this tournament."

There are political overtones off the field, and the game is being played on Sept. 11. On the field, North Korea is a threat to wreck the Americans' bid for a third World Cup before it barely begins.

Led by strikers Abby Wambach and Kristine Lilly, the No. 1-ranked Americans are the favorites. They are unbeaten in 2 1/2 years under Ryan, surging to the top of the world ranking ahead of No. 2 Germany, the defending champion.

Former Kahuku and University of Hawai'i player Natasha Kai is a member of the U.S. team.

Germany opens the three-week tournament against Argentina tomorrow in Shanghai. The final is Sept. 30 in Shanghai. Three other cities also host games: Tianjin, Wuhan and Hangzhou, with 2008 Olympic host Beijing left off the rotation.

By bad luck, and some unexplained maneuvers by FIFA, the Americans are stuck in the toughest of four groups. Joining them in Group B are No. 3-ranked Sweden, No. 5 North Korea, and African champion Nigeria. A loss to North Korea could be overcome, but it will make the route to the quarterfinals very difficult.

It's no stretch to suggest the U.S.-North Korea matchup may be the best of the tournament. Both teams attack relentlessly, their defenses are organized and North Korea striker Ri Kum Suk is a match for Wambach and Lilly.

"She's a true superstar player," Ryan said of Ri. "She has the same kind of impact on her team that Abby Wambach and Kristine Lilly have on our team. She's great on the dribble, great in the air like Abby and she creates like Lil."

Ryan has been preaching about North Korea to his relatively young team.

"We know they are very quick, they turn on a dime," defender Christie Rampone said. "They are definitely a counterattacking team that tries to catch you sleeping."

Wambach is America's go-to striker, a natural finisher with 77 goals in 96 games. Alongside is 36-year-old Lilly, who played in the inaugural World Cup in '91, which the Americans won.

She's played in 331 games, scored 126 goals and is the only player who has competed in every women's World Cup. That will be five, and only two men can match that: Mexico's Antonio Carbajal and Germany's Lothar Matthaeus. She's also played in every U.S. World Cup game and in every Olympic gold-medal game.

Stalwarts like Mia Hamm, Julie Foudy and Brandi Chastain retired after the United States won gold in the 2004 Olympics. Lilly is the old link on a younger team looking for its own identity.

"We're anxious for the first game," Lilly said. "The nerves are going to be there. They are going to be there for me, even though it's my fifth. I haven't seen a difference compared to the younger ones. I'm just as excited as they are."

This group may be better than any previous U.S. team. They are unbeaten in 46 games (39 wins, 7 draws and 0 losses) under Ryan. The only blemish is a penalty-kick loss to Germany in the 2006 Algarve Cup. The game was 0-0 after regulation and extra time. Because it was decided on penalties, it goes into the record books as a draw.

North Korea and the United States trained Sunday in Chengdu's 38,000-seat stadium. The Koreans rushed away with coach Kim Kwang Min offering only a few words to chasing reporters.

"Next time I will speak, next time," he said through a translator. On board a bus, his players waved, smiling for a few cameras.

The United States has played North Korea only twice; both in World Cup games, and both were 3-0 victories. The last was in the 2003 World Cup in the United States, a game the Americans were lucky to win.

The Americans scored on a penalty and two corners. North Korea missed early on two headers, and a couple of shots went off the woodwork.

"You look at results and you see 3-0. You kind of forget what the actual game was like," said Heather O'Reilly, who is likely to start up front with Lilly and Wambach.

The Americans face Sweden on Friday in their second game, and then finish group play in Shanghai against Nigeria. If they reach the quarterfinals, Germany or England from Group A will probably be waiting. Lurking in the weaker half of the bracket are Norway, China and Brazil.

The United States is likely to start five players new to the World Cup, but several are back from what Wambach called "a heartbreaking loss" four years ago to Germany in the semifinals.

Rampone was also there.