Martins, a 29-year-old Brazilian, is the second starter to have such an injury, joining winger Paul Arriola, who was hurt in a preseason friendly.
Martins’s injury came one day after Edison Flores, United’s marquee signing last winter, underwent surgery for facial fractures, suffered in a head-to-head collision last week. The Peruvian attacker is out four to six weeks.
Starters Russell Canouse, Steven Birnbaum and Frédéric Brillant, as well as reserves Oniel Fisher and Chris Odoi-Atsem, are also recovering from injuries. Brillant appears to be the only one who might return Wednesday night against the New York Red Bulls in Harrison, N.J.
Martins played every minute in his seven starts this season and was a regular in the lineup since being acquired in a trade with the Vancouver Whitecaps 13 months ago. With Birnbaum sidelined Saturday, he served as team captain.
Martins is the only D.C. player to record multiple assists this year, both coming against Toronto FC at the MLS is Back Tournament in Florida.
In his absence, Mohammed Abu is the leading candidate to partner with Júnior Moreno in defensive midfield. Moses Nyeman, a 16-year-old homegrown rookie who made his MLS debut last weekend, is also in the mix.
Because of the torrent of injuries and goalkeeper Bill Hamid’s absence for personal reasons, United had only 17 players available last Saturday for a 4-1 defeat at Philadelphia. Hamid returned to training this week.
On Monday, United bolstered the attack by signing Venezuelan striker Gelmin Rivas, a free agent who had most recently played in Turkey. However, he is ineligible until his work visa and international transfer certificate are approved.
United (1-4-3) is winless in six straight, the only victory coming at home in March against expansion Inter Miami before the coronavirus pandemic forced MLS to suspend the season.
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