NEW YORK -The Seattle Sounders have become the first team to qualify for the 2010-2011 CONCACAF Champions League, cementing their place by beating D.C. United to win the U.S. Open Cup.

The Sounders' 2-1 victory in Washington Wednesday night made it the first team to clinch a place in the 24-team field and claim the first of four berths from the United States.

"With their average attendance this year, the Sounders will be a great addition to the Champions League," CONCACAF General Secretary Chuck Blazer said. "We can't wait to have them."

Seattle, competing in its first season in Major League Soccer, has led MLS with an average crowd of 30,587 playing at Qwest Field, more than 10,000 better than the next best team: Toronto FC (20,308).

Freddy Montero and Roger Levesque scored second-half goals to give the Sounders, led by goalkeeper and former U.S. national team veteran Kasey Keller, a 2-0 lead before Clyde Simms tallied in the 89^th minute to set off a furious push in injury time by D.C. United.

D.C., which is involved in the Group Stage of this year's CONCACAF Champions League, was seeking a third straight berth in the confederation club championship and still can claim either the other Preliminary Round berth or one of the two Group Stage places in 2010-2011 through the campaign of the MLS regular season and MLS Cup playoffs.