Union designated player Maurice Edu has yet to practice with the team following sports hernia surgery, and his availability for the March 6 Major League Soccer opener at FC Dallas is in doubt.
"The fact that he hasn't been on the field, you can read into what you want," coach Jim Curtin said on Tuesday in a conference call. "It would be tough" for him to play on opening day.
Curtin wouldn't say for sure that Edu, who is returning to the midfield after playing center back last year, will be unavailable for the opener.
"If anybody can do this, it's Mo, who is a freakish athlete who has played through pain.