In a stunning move, the Washington Diplomats yesterday acquired Dutch superstar Johan Cruyff in an attempt to bolster the North American Soccer League team for its stretch drive as well as improve attendance.

Cruyff will join the Diplomats on July 1 for their game in RFK Stadium against San Diego. Cruyff, who was a free agent in the NASL as a result of being put on waivers by the Cosmos, to whom his contract reverted after the old Diplomat team folded following the 1980 season, will play the rest of this season and has an option to play with the Dips in 1982.

Terms of Cruyff's contract were not revealed, but it was learned he would not make as much as the reported $600,000 he was paid to play here last season, when he scored 10 goals and had 20 assists.

His return here was the result of a last-minute deal engineered by the Dips' principal owner, Jimmy Hill.

Cruyff, 34, reached a verbal agreement with Hill and his son Duncan, the team's general manager, late Tuesday night just minutes before the NASL's midnight deadline on overseas transfers.

"The odds of us signing Johan were 50 to 1 against when we started three days ago," Jimmy Hill said, "and 8 to 1 against on Tuesday night."

Cruyff, acknowledged as one of the best players in the world the past three years, was playing in a tournament in Milan, Italy, and could not be reached for comment last night.

He just finished the season with Levante, a second division team in Valencia, Spain, where he didn't play especially well. Cruyff is said to be recovering from groin surgery and will rest a week before arriving in Washington on June 28 to 29.

Gary Lemmen, a limited partner in the Diplomat organization said the acquisition of Cruyff is expected to "attract 3,000 to 5,000 more customers per game." Coach Ken Furphy said at a hastily called press conference before last night's 2-1 loss to the Cosmos that he is not sure what position the forward/midfielder will play once he joins the team.

Cruyff's contract was assumed by the NASL champion Cosmos after Sonny Werblin, president of Madison Square Garden, and Gulf and Western folded the team last November. But the Cosmos didn't approach Cruyff and he was declared a free agent.

Furphy, both Hills and Lemmen looked tired and drawn from the nearly all-night Tuesday and all-day Wednesday negotiations they carried on with Cruyff.

Partly responsible for the marathon negotiations was Washington's desire for Cruyff to be under contract exclusively to the Dips. Cruyff agreed.

"The only stipulation he asked for," said Duncan Hill, "was that he wanted to rent the house he had here before. I was staggered."

Hill said repeatedly during the team's first few weeks in Washington that he would refuse to pay some ridiculous price for a superstar when the team the club was fielding was playing so well.

"For the last few weeks it's been on our minds a lot," Duncan Hill continued. "But only in the last three days since Jimmy has been here have we really thought it could happen. It's marvelous for the franchise.

Furphy said he began thinking more seriously about getting Cruyff after evaluating his current roster (9-7, in second place in its division).

Both Duncan Hill and Furphy said several times early in the season that they'd rather not build the team around one superstar, but instead opt for total team play. That would leave the team free of tension and save the franchise dollars.

Duncan Hill said the approach for dealing with Cruyff was "to very quickly and sensibly say what this franchise could afford to spend but at the same time compensate for the best soccer player to play in North America."

Said Striker Paul Cannell, "I knew they were playing the Maryland Lottery. But I didn't know that they hit it."

Though the term has had big crowds for the two Cosmos' home games, the club has averaged less than 12,000 per game; last year's Dips averaged 19,000.

"I'm a businessman," said Lemmen, who flew here from Bloomfield, Mich., Tuesday night. "And I'm looking at dollar counts and revenue. I don't want to be another folded-up team in the NASL. We welcome Johan Cruyff with open arms."

While considered by many to be among the most skillful, artistic and electrifying playmaker in soccer history, Cruyff's ability to get along with his teammates has been strained at times. He openly fueded with Coach Gordon Bradley and other players last season, contributing to a disappointing 17-15 season.

"I never had any problems with Pele or Trevor Francis," said Furphy, referring to the strong-minded superstars he coached with the Cosmos and the Detroit Express. "If there's any problem, I'll solve it."

Forward Don Nardiello said he expects Cruyff to fit into the team concept already formed and not cause any problems.

Cannell, whom Cruyff replaces as the highest-paid and likely most popular Dip, said he hopes Cruyff and the team will adjust to each other faster than the 14 to 15 games it took the old Dips last season: "If it takes us that long, we're gonna be in trouble."