An early look at the Sounders' first meaningful international match in club history:
AD ISIDRO METAPANSEATTLE SOUNDERS FC7 p.m. Tuesday, Estadio Cuscatlan, San Salvador, El Salvador.TV: Fox Soccer Channel.ABOUT CONCACAF CHAMPIONS LEAGUE: The competition brings together 24 club champions from North America, Central America and the Caribbean. Seattle qualified by winning the 2009 U.S. Open Cup. This is the second game of a two-game preliminary round series, which will be settled by aggregate score. The winner advances to the group stage, with the top two teams from four four-team groups moving on. Clubs use 18-man game day rosters, three substitutes per game, and yellow-cards accumulate from game to game.ABOUT METAPAN: The club was formed in 2000, when two earlier clubs merged into Asociacion Deportiva Isidro Metapan. Based in Metapan, El Salvador, the club has won four first-division titles over the past seven seasons. This is its third Champions League appearance. Edwin Portillo has been the manager throughout that run.NOTES: Seattle won the opener, 1-0, last week at Qwest Field. That, in effect, puts them one-goal up halfway though a 180-minute competition. Road goals are used as the first tie-breaker. If that doesn’t determine a winner, the game will go to 30 minutes of extra time; then, if necessary, penalty kicks. … The game was moved to Estadio Cuscatlan because the lighting at Metapan’s small home stadium was judged insufficient. … Seattle is unbeaten in six straight games over all competitions. … Sounders FC put midfielder Peter Vagenas on the MLS disabled list Monday, citing a right quadriceps strain. That list does not affect CONCACAF competition, but Vagenas, 32, will have to miss at least six MLS games. He will be eligible to return for the Sept. 9 game against the Real Salt Lake. NEXT: Seattle returns to league play at 8 p.m. Sunday vs. Houston at Qwest Field.