D.C. United forward Fabian Espindola is set to miss 2-4 weeks with a hamstring injury.
Espindola was injured in Saturday's 3-0 win against the New England Revolution and was replaced by Alvaro Saborio.
United coach Ben Olsen told the Washington Post that Espindola will have an MRI scan on Tuesday.
"Hopefully, we get a surprise and it's a mild injury," Olsen said.
Espindola has scored three goals in five starts after missing the start of the season with another hamstring injury.
With Espindola out, Boca Juniors loanee Luciano Acosta scored his first goal of the season against the Revs. He's played the past five games as a substitute after starting the first three.
"Acosta has done a good job off the bench but so has Saborio," Olsen told the Post. "They are different in their traits. It's next man up, and a lot of guys want more playing time.
"It's why we have built a fairly deep squad and hopefully the next guy up can do the job and continue the little bit of momentum we've built the last few games."