Here's some good background information on CONCACAF Champions League in general and Sounders-Metapan in particular, from Sounders FC:
About MetapánAD Isidro Metapán won the 2010 Clausura for its fourth title in the last seven seasons (there are two seasons per year in El Salvador's Primera División). That season concluded with the final on May 23. All of the championships have come under coach Edwin Portillo, who also played 10 years for Los Caleros. The 2010 Apertura begins August 8 at Alianza. Metapán was 5-2-8 in league play and then advanced over Firpo (4-3 on aggregate) and Aguila in the playoffs. Mark Blanco scored two first-half goals in the final with Aguila. Elias Montes scored the deciding goal in the 81st minute of the second leg semi at Firpo. Metapán was 3-0-5 at home and drew 2-2 with Firpo in the semifinal first leg at home, the 8,000-seat Estadio Jorge Calero Suarez. The August 3 match with Sounders FC will be played at the Estadio Cuscatlán, the 44,000-capacity national stadium in the capital city of San Salvador. It is also the home pitch for Alianza. Metapán is located in the northwest corner of El Salvador, approximately 50 miles travel from San Salvador by road. Metapán's home stadium, Estadio Suarez, was not approved as a suitable site by CONCACAF, prompting the move. Awaiting the WinnerThe winner of the Sounders FC-Metapan series advances to the group stage, joining Monterrey (Mexico), Saprissa (Costa Rica) and the winner of the preliminary round matchup of Tauro (Panama) and Marathon (Honduras). Marathon and Tauro meet Wednesday and again August 4. In group play each team plays one another twice, home and away. Seattle would visit Marathon or Tauro on August 19 and host Monterrey on August 25. The remainder of the group stage schedule will be announced following completion of the preliminary round.Past Champions
Several members of the Sounders FC have tasted success in the Champions League predecessor, the CONCACAF Champions Cup. Ezra Hendrickson, now an assistant coach, scored two goals in the 2000 Final as the L.A. Galaxy defeated Olimpia of Honduras, 3-2, at the Coliseum. Peter Vagenas was a teammate of Hendrickson and Sigi Schmid was the Galaxy coach.From Here to There
Sounders FC qualified for the CONCACAF Champions League by winning the 2009 Lamar hunt U.S. Open Cup. The other U.S. berths went to Real Salt Lake (MLS Cup champion), Columbus Crew (MLS Supporters' Shield winner) and L.A. Galaxy (MLS Cup runner-up). The former two receive automatic passage to the group stage. Toronto FC is Canada's representative. The CONCACAF Champions League is open to the leading teams from federations throughout North America, Central America and the Caribbean.Pachuca of Mexico won the 2009-10 CONCACAF Champions League. It finished tied, 2-2, on aggregate with Cruz Azul, but prevailed on away goals. Pachuca will represent CONCACAF in the 2010 FIFA Club World Cup in Abu Dhabi, United Arab Emirates in December. Barcelona is the reigning world champion. The Champions League consists of three stages: preliminary rounds, group play and knockout rounds. Group play will begin in mid-August and conclude in late October. Two teams from each group advance to the quarterfinals, to be played in February 2011. The quarterfinals, semifinals and final are two-match series with the winner determined by total aggregate goals. Away goals will be used as the tiebreaker. If teams remain tied after extra time in the second game, the outcome will be decided by penalty kicks.Champions League Experience
Altogether, seven current Sounders FC players have seen action in Champions League or Champions Cup competition previously in their career: Patrick Ianni (HOU 2007-08), Nate Jaqua (CHI 2004, HOU 2008), Tyrone Marshall (LA 2003, 2006), Pat Noonan (NE 2003, 2006), James Riley (NE 2006), Nathan Sturgis (LA 2006) and Peter Vagenas (LA 2000, 2003, 2006). Sigi Schmid coached the L.A. Galaxy during tournament appearances in 1999, 2000 and 2003.Memories of San Salvador
Both goalkeeper Kasey Keller and central defender Tyrone Marshall have played international matches at the Estadio Cuscatlán. Keller earned the shutout in a 2-0 win for the U.S. National Team during World Cup qualifying in 2004. Tyrone Marshall was in the Jamaica XI for qualifiers in both 2000 and 2004. Sounders FC technical director Chris Henderson was a USMNT starter and served as captain in 1993 when the Stars and Stripes drew, 2-2, in a friendly with El Salvador.
Mexico's Cruz Azuland Club American each have five CONCACAF championships. Defending champion Pachuca has won four times, all since 2002. Mexican clubs have dominated the tournament, winning 27 titles since it began in 1962. The only two U.S. clubs to win were D.C. United (1998) and the L.A. Galaxy (2000). No MLS side has advanced to the final since 2000 and none have won a quarterfinal since 2008.Sounders in CONCACAF Past
This marks the second CONCACAF involvement for a Seattle professional team. The Sounders qualified as the U.S. representative in 1996 as A-League champions. Seattle defeated Surinam's Transvaal in the preliminary round then finished fourth in the final group stage, won by eventual champion Cruz Azul.