Audi Field, as of Dec. 14. (D.C. United)

MLS is almost ready to announce the 2018 home openers for all 23 teams, but with Audi Field not scheduled to open until the summer, the location of D.C. United’s first home match — and a few additional games — remains unclear.

In all likelihood, the league will soon set United’s first date and opponent without identifying the location. The club would then continue weighing stadium options and announce the venue in subsequent weeks. MLS is aiming to announce the home openers before Christmas and the complete schedule sometime next month.

United has been lobbying to play every home match at the 20,000-capacity stadium in Southwest D.C., packing 17 games into the last four months of the season. As we’ve reported, however, the league is reluctant to do so because of scheduling complications and concerns about affording one team a long stretch of home dates during the last part of the regular season.

So United has been exploring opportunities, from Delaware to North Carolina, in anticipation of having to play between two and four off-site home games between early March and early June. Without any home dates, D.C. would end up playing at least 12 consecutive away matches to start the year; the league record is 10.

MLS is expected to mandate the exact number of alternative home games for United in the coming weeks.

Both the team and league have known since last winter’s groundbreaking that Audi Field would not be ready until summer 2018; the tentative debut is June 30. Construction is on schedule, United officials say.

With the schedule in flux, the team did not want to comment at this time on the prospects of playing at secondary venues. However, it’s becoming clearer which locations are in the running and which have been ruled out:

* Annapolis: Navy-Marine Corps Memorial Stadium appears to be a front-runner for at least one game. An academy spokesman said last month that the sides have engaged in talks.

Positives: It’s in the metro area (30 miles from D.C.), provides a nice day outing for fans from near and far, and the venue size is suitable for United’s purposes (34,000 capacity).

Negatives: artificial turf and possible scheduling conflicts with the Navy men’s and women’s lacrosse teams, which are home on several Saturdays: March 10, 17 and 31, and April 7 and 28. (United could play on a Sunday.) In addition, the Washington Capitals will play the Toronto Maple Leafs in an NHL outdoor game March 3. (The MLS season commences March 2-4.)

* College Park: It’s a great location, just inside the Beltway, but comes up short in critical areas. Capitol One Field at Maryland Stadium, a 51,000-seat football venue, is too narrow for soccer standards. It’s also covered with artificial turf. Across the parking lots, Ludwig Field, home of the soccer programs, can accommodate only about 7,500 and lacks proper locker rooms and other infrastructure.

* Montgomery County: The stadium field at Maryland SoccerPlex in Boyds offers a flawlessly manicured grass surface and a lovely, relaxed setting with seating areas on a grass embankment behind one goal. However, with a capacity of 5,200, it would not generate the necessary ticket sales and game-day revenue. United has played many U.S. Open Cup matches there over the years, but those tournament games are outside normal scheduling and don’t figure into regular season budgeting and revenue.

* Richmond: It’s 110 miles, but on most traffic-jammed days on I-95, it feels like 1,100. So if United decided to play at City Stadium, home of its second-division affiliates known as the Kickers, the club would have to market primarily to fans in the Richmond and Hampton Roads areas. The stadium is capable of holding 22,000 spectators, but one side is no longer in use and would require upgrades. Consequently, United would have to aim for a capacity crowd of about 10,000.

* Washington: The Nationals, who will become United’s neighbors when Audi Field is complete, apparently have no interest in disrupting baseball operations for a soccer match. Even if they were open to the idea, United would probably balk at the cost.

Meanwhile, RFK Stadium, where United played for 22 seasons, sits vacant. It would be logistically seamless for the club, which will continue using the locker room, weight room, basement offices and practice fields for at least another year or two until ownership builds a training facility.  However, RFK is not preparing the field for any sporting events in the near future. One source familiar with the situation said United would play at RFK again “only in the case of emergency.”

* Baltimore: United has had conversations with the Orioles about playing at Camden Yards, which has never staged a soccer game. But those talks have not made much progress. M&T Bank Stadium, an occasional international soccer venue, will undergo further renovations during the NFL’s offseason.

* Landover: United has apparently had no talks with the Redskins about using FedEx Field, which is too large for its purposes and expensive to rent.

* Elsewhere in the Mid-Atlantic: United has considered WakeMed Soccer Park, a 10,000-seater with grass in the Raleigh suburb of Cary, N.C., and Delaware Stadium, a 22,000-capacity, college football venue with artificial turf. However, Newark, Del., is deep inside the Philadelphia Union’s marketing territory.

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