Three months ago, Washington Diplomat fans had visions of their darling team, now loaded with such international stars as Johan Cruyff, Wim Jansen and Juan-Jose Lozano, challenging the three-time NASL champion Cosmos for the Eastern Division crown.

A poor start and a bundle of injuries reduced the Dips to an average team, while the talent-laden Cosmos ran away to an easy third straight division crown.

"This Sunday's game would have been a big one, if our season had gone as we had hoped it might," said Dip defender Don Droege during yesterday's practice at Georgetown's new AstroTurf facility. "But we didn't get off to a good start and we have to be content with finishing second. I'm not disappointed in that but I am disappointed in our record."

Droege and his teammates will battle the 22-7 Cosmos Sunday at the New Jersey Meadowlands at 7:30 as if a title was on the line.

"We haven't actually clinched second yet," said Washington striker Alan Green. "We still need 12 points, so we need a win. This game is important to us. We want to get that win now to secure that spot for the playoffs."

Washington, which has 134 points, 16 ahead of third-place Toronto, can rest assured the Cosmos will not take it easy, although the game means nothing to the home team, in terms of the standings. For one, more than 50,000 are expected to watch Cruyff and the Cosmos will do nothing in their power to shut down the Dutch midfielder and the Dips. The Cosmos rarely lose at Giants Stadium and own a 9-3 lifetime advantage over Washington.

"The game doesn't mean anything to them but I don't expect an easy game," said Dip Coach Gordon Bradley. "Just because we have Johan, they'll play us rough. They need momentum too.

"The game means second place for us. We lost our last two games, although I felt we played very well. We're playing good attacking soccer and in the Minnesota and Vancouver games I thought we ran into the best two goalkeepers we've seen all season. But we're all right. We're almost completely healthy and we're looking toward the Cosmos."

Washington ran through a spirited one-hour scrimmage yesterday in preparation for what is expected to be a physical battle at Giants Stadium.

The last time these clubs met, the Cosmos managed a 2-1 triumph in a shootout before an RFK soccer-record crown of 53,351. The game was spiced with several rhubarbs involving players, fans and the officials.

The Cosmos' Giorgio Chinaglia leads the league in scoring with 29 goals and 11 assists for 69 points. Green is fourth with 23 goals and eight assists for 54 points . . . . Green also is the club leader in shots taken with 136, eclipsing his own 1979 mark of 121 . . . . Following the Cosmos game, the Dips will close out the regular season at home against New England and Minnesota.