For the past several weeks the Washington Diplomats' coach, Gordon Bradley, has been saying that his players have an advantage playing at home because they are used to the humidity that seems to blanket RFK Stadium during much of the North American Soccer League season.

Tonight, the Diplomats walked into the oven known as Atlanta Stadium and realized that they would get no help from the weather when they take on the Atlanta Chief's Wednesday at 7:30 p.m. (WTTG-TV-5)

"This is unbelievable," said Bradley as he walked onto the steamy field to watch his team practice. "I thought RFK was hot, but this feels much worse."

The reason is simple: Atlanta has all of Washington's heat and humidity -- 97 degrees today with 65 percent humidity -- and the Chiefs play on a field below ground level and untouched by breezes.

As a result, the Dips, who have a 19-9 record, good for 169 standings points, must be wary of the Chiefs, 11-17 for 112 points but owners of impressive victories in this hotbox.

"Their offensive talent is unquestionable," said Bradley. "Jeff Bourne is as good a goal scorer as there is in this league. If you look at their statistics, when they win, they win big. Especially here."

The chiefs, formerly the Colorado Caribous, despite being six games under .500, have scored as many goals, 55, as they have given up. They have won games by scores of 4-0, against Tampa Bay; 5-2, Minnesota; 4-1, Chicago and 6-0, Memphis.

"Their record is deceiving," said Bradley, "because they were 2-10 and then started to play well. They always had the offense. When they got Victor Nogueira in goal, it made a big difference for them. Since he came in they are 9-7. And if they could ever win in a shootout (the Chiefs are 0-4) they'd probably be in the playoffs."

The Chiefs are mathematically not out of the playoffs but largely because they dropped a 2-0 decision to lowly Memphis here Sunday have practically no chance of getting there.

"That (the loss) was a big disappointment for all of us," said striker Neill Roberts, who joined the Chiefs 17 games ago and has scored 14 goals while relieving some of the pressure on Bourne, who leads the club with 17. "We seemed a bit overconfident because we had beaten them, 6-0, on their field.

"I think we may have been looking ahead to the game with Washington as a kind of showdown for us. They beat us, 5-1, the first time (April 1) and even though I wasn't here, I know the players who were are looking for a bit of revenge.

The Dips' playoff situation, complex a week ago, has become rather simple. A victory here and against the Cosmos in New Jersey Sunday would give them in the second best record in the National Conference, meaning they would have home field advantage for at least two rounds in the playoffs.

But Minnesota, just three points behind Washington, plays its final two game2 at home, against Detroit and Memphis. That means the Dips almost must win to remain ahead of the Kicks. Having the home field for a possible second round match with Minnesota is extremely important to Bradley, especially since the Kicks are 12-1 at home this season and beat the Dips, 3-1, there in July.

Bradley will use the same lineup against Altanta that started against Toronto, unless midfielder Sonny Askew is still bothered by a pulled leg muscle In that case, Rene Breevoort probably will start in his place.

Bobby Stokes and Alan Green, with six goals the last two games, will start up front and Bill Irwin, with a 1.27 goals-against average, will be in goal for the 27th time in 29 games.

"Well," said Green sweating in the heat, "we should feel right at home playing on this field. But, then again, so will they."