By Paul Kennedy in Seoul Daegu suddenly becomes the place to be Monday afternoon: South Korea-USA, the meeting of the surprise leaders of Group D. The U.S. players and coaching staff tried to put the big win over Portugal quickly behind them. Coach Bruce Arena said he was in bed by 11 o'clock. ''You've got to look forward,'' said Arena. ''You can't live on that day.'' The United States will face several big challenges. South Korea has the home-field advantage. The support of the Red Devils, Korea's supporters, has been one of the big stories of the World Cup. Arena said his players were not intimidated by playing in such an atmosphere. ''Playing in Mexico City at Azteca Stadium with 110,000 fans is like you're [being swarmed by] bumble bees,'' said striker Brian McBride. South Korea will have an extra day of rest, and the match will be played in the afternoon in Daegu, one of Korea's hottest cities. Arena dismissed the effect the conditions will have on the team, but he said that the game would not played at the same pace as the USA-Portugal. ''The game is not going to be played at a frantic pace, regardless of the fitness level of the players,'' Arena said. Still, the Korean pressing game is expected to test the United States, especially in the back. Besides changes in the U.S. lineup based on fitness questions — Claudio Reyna possibly returning and Earnie Stewart possibly being out — Arena may make some changes to keep his players fresh. The key game may not turn out to be the Korea game. It could be the Poland game. If the U.S. needs a win in the final group game, Arena will need enough players with something left to challenge the physical Poles.