There is no doubt that the Washington Diplomats pulled off a substantial coup. John Cruyff, though 32, remains one of the most magnetic and brilliant soccer players in the world. With Franz Beckenbauer, also to be found now in the North American Soccer League, he is one of the two great innovators of modern football, the men who invented total soccer, the tactics whereby (at least in theory) anyone should be capable of doing anything.

That Cruyff is still playing may have something to do with his love for the game. But probably a great deal more, alas, with the fact that while playing for Barcelona -- as has been well publicized and documented -- he had several business setbacks, incurred the wrath of the Spanish tax authorities, and found himself, like Pele before him, drawn to the United States: He needed BIG money.

Even as recently as 18 months ago, at Chelsea, the Southwest London club, Cruyff, playing as a guest for the Cosmos, charmed and fascinated the crowd with his brilliance. He is a center forward who is much more than just a center forward, a playmaker as well as a goal scorer, a footballer who thinks like lightning and at his best moved almost as fast: Though he has always said that he was not especially fast, he merely made up his mind much quicker than his opponents.

Though humbly born -- his mother used to clean the floors of the Ajax Soccer Club in Amsterdam where he began -- Cruyff is a natural polyglot. In training camp during the last World Cup, there he was among German-, Italian-, Spanish- and English-speaking journalists, addressing each in turn in his own tongue.

Never has he played better than in that 1974 World Cup, twisting and turning through defenses in his electric way, so very hard to stop, although there is so little, physically, of him. But he was working out the most marvelous, simple, sweeping attacks with Johan Neeskens (he too is in the States (now). What a wonderful goal they scored in the rain at Dortmund against Brazil, breaking away, Cruyff on the right wing, Neeskens giving him the ball and racing through the middle, getting it back perfectly in his stride to sweep it past the goalkeeper.

Cruyff inspired Ajax to win the European Cup three times in a row, and when he left for Barcelona in 1973 for a massive salary and at a huge transfer fee, it was significant that Ajax never won it again. He took as his idol the Argentine center forward Alfredo di Stefano, who inspired the Real Madrid team which won the first five European Cups in a row. They have certain skills in common, together with the fact that neither was a great header of the ball. But di Stefano took the whole field as his province -- a defender, playmaker and goal scorer.

Cruyff, who did not play World Cup in 1978 because he did not wish to be away from his family, essentially does his best work at the front, or just behind the firing line.

On the field he can be an imperious, impatient figure. There is surely no love lost between him and the new coach of the Cosmos, Hennes Weisweiler. At Barcelona, the two locked horns. Cruyff had begun superbly there, joining the club in midseason, inspiring them to zoom up from the bottom of the table to win the championship. Thereafter he was a marked man, kicked regularly by callous opponents, unprotected by feeble referees. Time and again he fell afoul of those referees. Weisweiler implied that Cruyff had lost his appetite for going up into the front line, the cauldron of the opposing penalty area, and risking hard knocks. Who would blame him if it were true?

Bitter relations ensued, until the prsident of the club had to choose between the two. He promised to back Weisweiler, but Cruyff was just too popular in Barcelona to be (Billy) Martinized. The public was vigorously, even violently, on his side and it was Weisweiler, deeply resentful, who went.

Cruyff can easily play another three or four years in the NASL, if he wants. The owners of the Diplomats dug deep into their vault to buy him from the Aztecs for $1 million, and meet his price of about $500,000 a year.

But it was a smart move by the Diplomats because with Johan Cruyff, who inspires any team he plays for, the Diplomats could upset the Cosmos as kingpins of the league.