Ready or not, Washington area sports fans will find themselves with another sport to contend with next month - indoor soccer.

Only five of the North American Soccer League's 22 teams have formally agreed to field teams. The Washington Diplomats, at the urging of general manager John Carbray, will play a nine-game indoor season beginning Jan. 7 in the D.C. Armory.

Eight of the nine games will be played at home.The games will mean nothing. There is no league, no tournament, no playoffs. Teams will play for little more than bragging rights.

But Carbray, chairman of the league's indoor committee, has been a staunch supporter of the indoor game, and insists there's more to it.

"I've always maintained that one of the biggest problems the league has, and one of our problems too, is visibility," he said earlier this week. "We've visible for four months and dormant for eight. Other sports are the other way around.

"We want people to remember the Dips. We want them to keep in the habit of coming to see the Dips play. This gives the fans something to talk about and the media something to write about. It gets people thinking about soccer."

How many people will be thinking soccer is the question. The Dips spent in the neighborhood of $25,000 in purchasing an AstroTurf carpet from the Dallas Tornado and plexiglass from Philadelphia. Purchases new, these items would have cost $75,000, according to Carbray.

Add rent to the Armory to the usual expenses involved with fielding a team, and Carbray concedes the Dips will need to average at least 5,000 fans a game in the 10,000-seat arena if they are to break even.

"I think we can draw that many if we get off to a good start," he said. "We're hoping people will come out at first because it's something new. If things go well, we think they'll come back."

Indoor soccer is very different from the outdoor game. The size of the playing field, 200 feet by 85 feet, makes for much more scoring, in the neighborhood of 12-16 goals in an average game. Goalkeepers are almost helpless in the confined playing area.

Hockey rules are used: penalties send a man off the field for two minutes; play is continuous unless the ball leaves the playing area; substitutions can be made on the fly, and six men, including the goalkeeper, play on a side. Games are standard soccer length, 90 minutes.

The Dips will play four two-game weekend series at home. They will open on Jan. 7 at 8 p.m. against the Fort Lauderdale Strikers. The next afternoon at 3 p.m. they will face the Strikers agaiN.

The rest of the home schedule includes games with the Tampa Bay Rowdiets on Jan. 28-29; the Dallas Tornado Feb. 11-12, and the Chicago Sting Feb. 25-26. The only road game will be against Tampa Bay in St. Petersburg on Feb. 3. The reason for the lack of road games is simple: At the moment, Washington and Tampa Bay are the only teams hosting indoor games.

Carbray insists that there are two very good reasons for following through with an indoor schedule even though enthusiam for the sport around the league appears minimal.

"First of all, it gives us a good springboard for the outdoor season," he said. "And second, a lot of teams who were against the concept now say they're interested and if they don't come in this season, they might come in next."

Keeping soccer visible during winter months seems logical. Whether the Dips, still struggling to establish themselves at the gate outdoors, can draw indoors, is a major question mark.

In addition, even though he won't admit it publicly, it seems apparent that coach Gordon Bradley is less than thrilled with the indoor schedule. He feels this time could be better use putting together an outdoor team at this time of year.

Bradley's feeling are perhaps best summed up his former boss, New York Cosmos president Ahmet Eretegun. When asked why the Cosmos weren't getting into indoor soccer, Ertegun answered, "We still have a lot to worry about and work on outdoors. We want to get that right before we try to work indoors."

That is basically Bradley's attitude. But Carbray wants an indoor schedule and he will have one, league or no league. There is some feeling among Dip players that Carbray would have staged intrasquash matches if necessary in order to have indoor soccer.

The NASL held indoor tournaments in 1975 and 1976 but has never had an actual league schedule. Carbray hopes that will come about in 1979. He said he feels if the 1978 season is a success, many more teams will show an interest a year from now.

"This indoor season may not mean all that much by itself," Carbray conceded. "But in terms of what it can do for the outdoor season, for the organization and for the potential indoor has in the future, it's worth it."