 Seattle won the 2009 U.S. Open Cup — the second MLS expansion club to do so in its inaugural season after the Chicago Fire in 1998 . Prior to the final , Sounders FC played U.S. Open Cup home games at the Starfire Sports Complex in Tukwila , Washington . The facility is smaller than the club 's home stadium for league matches , Qwest Field , but Sounders FC representatives preferred the atmosphere at Starfire for smaller cup matches . 
