Seattle Sounders FC operates Tacoma Defiance in MLS NEXT Pro, the league second-division developmental league. MLS NEXT Pro serves as the primary pathway for young players to develop and earn minutes in a competitive professional environment before graduating to the first team.
The reserve team structure allows clubs to bridge the gap between their academy programs and the first team. Young homegrown players can gain valuable experience against professional competition, while first-team players returning from injury can use reserve matches to regain fitness and sharpness.