SEATTLE – Seattle Sounders FC’s gripping win Tuesday over Mexico’s Tigres UANL in the CONCACAF Champions League quarterfinals won’t soon be forgotten.

 History makes it so. No MLS team had ever beaten a Mexican team in the CCL knockout rounds since the tournament changed formats in 2008-09. Only one MLS team had ever bested a Mexican team in a top club competition in the region (Kansas City beat Santos Laguna in the 2002 CONCACAF Champions Cup).

 Support for Seattle poured in from across the league – including the commissioner and even conference rivals – after the breakthrough victory.

 “It is a story you can pass on to your kids and grandkids and it makes the city proud,” said defender DeAndre Yedlin, who scored the first of three goals in Seattle’s comeback from a two-goal series deficit.

 The story can still get better. The Sounders could become the first MLS team to win the tournament, with Mexico claiming all four winners and even three runners-up. The next step is a two-leg semifinal series against a familiar foe, Santos Laguna, which eliminated Seattle in the quarterfinals of the 2011-12 tournament, 7-3 on aggregate.

 Specific dates and times are to be determined, but the first leg will be at CenturyLink Field (April 2-4) and the second will be on the road in Mexico (April 9-11).

 “We’ve got a score to settle with Santos,” said coach Sigi Schmid.

 The Sounders could have their imminent acquisition settled by then as veteran forward Obafemi Martins told the BBC recently that he is just waiting to get his visa before coming stateside to officially sign with Seattle. The Nigerian international, who would be a designated player, paid the buyout clause of his contract with Spain’s Levante UD on Monday.