Washington Spirit midfielder Andi Sullivan will miss the rest of the season with a torn ACL, the team announced on Wednesday.
United States international Sullivan sustained the knee injury late in Sunday's 2-0 road loss to the Orlando Pride. Washington has three games left in the regular season.
Sullivan, 28, recorded two goals in 21 matches (all starts) this season, with the Spirit compiling a 15-5-1 record in those contests.
She has 16 goal contributions in 134 appearances across all competitions since Washington drafted her with the No. 1 overall pick in 2018.
Washington is already dealing with significant injuries less than a month before the playoffs. Forward Trinity Rodman (back) and defender Casey Krueger (adductor), who were both part of the USWNT's Olympic gold-medal winning team in August, have missed the last two games.
Colombian playmaker Leicy Santos also missed Sunday's match due to a thigh injury. Ouleymata Sarr, the team's co-leading scorer alongside Rodman with eight goals, has not played in over a month due to a back injury.
Earlier in September, the Spirit lost rookie midfielder Croix Bethune for the rest of the season to a torn meniscus that was sustained while throwing out a first pitch at an MLB game. Bethune, was also one an Olympic gold medal this summer, tallied 10 assists this year, tying Tobin Heath's single-season mark from 2016.
Sullivan has won 52 caps for the USWNT and appeared in all four games at the 2023 Women's World Cup, though has not featured for the national team since October of last year.
Information from ESPN's Jeff Kassouf and Field Level Media contributed to this report.