Major League Soccer does not want D.C. United to play their home opener at Maryland SoccerPlex because of facility and security concerns, sources told The Washington Post. No final decision has been reached yet, but if the plan is rejected, United would have to scramble to arrange another location for the March 17 match against the Houston Dynamo. Audi Field, the club's 20,000-capacity stadium in Southwest Washington, is on schedule to open July 14 after a 16-month construction timetable. The club has not publicly announced its plans, but since last month, it has been lining up the SoccerPlex for the home debut and Navy-Marine Corps Memorial Stadium in Annapolis on April 14 against the Columbus Crew. A league representative inspected both sites in recent weeks. The Navy venue is expected to receive approval. MLS's primary concerns with the SoccerPlex, sources said, are the absence of a proper referees' locker room — it must include a restroom — and the swirl of activity throughout the day at a complex with more than 24 soccer fields and other facilities. The MSI Cherry Blossom Classic, a youth soccer tournament, will run March 16-18. That would perhaps leave Maryland's Capital One Field, which has ideal infrastructure and no scheduling conflicts but an artificial surface with permanent markings.