The injury absence comes after his public criticism over a recent lack of playing time.
Saief left training Friday early because of the knock and received treatment with the other injured players this morning.
The Anderlecht loanee started six of eight matches with only a goal and an assist in his first start in a 2-0 win over the New England Revolution. He was an unused sub in a 2-1 win over the Montreal Impact on May 11 and came on for 25-minute substitute appearance in a 5-1 defeat at Orlando City SC last Sunday.
“I felt the past week I trained every day, which [some of] the other guys didn’t train the full days, and it’s not fair,” Saief told The Athletic. “I think the staff should have let me start above them, but I don’t know. It doesn’t matter. Whoever plays we should support them.”