When Cor van der Hart became coach of the Fort Lauderdale Strikers in January, he had one small problem:

"I didn't speak any English," van der Hart said in broken, but clear, English today. "We had players on this team from 12 different countries. A lot didn't speak English. We had some problems in the beginning."

If the Washington Diplomats, who play the Strikers here Saturday at 8 p.m. (WWDC-1260), could overcome their problems the way van der Hart has overcome his, they too might have a 7-2 record, instead of their own 3-4.

The 1980 Strikers have conjured up memories of the 1977-78 New York Yankees: They squabble, but they win.

During a preseason exhibition tour in South America, van der Hart argued publicly with players on several occasions. He was openly critical of them in the press. Now, he says, "That is all behind us."

Not quite. Thursday, backup winger Greg Villa showed up, according to witnesses, at 4:31 p.m. for a 4:30 practice. That wasn't good enough for van der Hart.

"That was the third time he's been late for practice," van der Hart said today. "You must have discipline on a team, or you have nothing. I sent him away from practice. He will not play against Washington."

Villa angrily protested his bouncing. "He's just completely unreasonably," he said of his coach. "I'd better not be fined for this."

Van der Hart has never claimed to be reasonable. At 52, he has been involved in soceer for 40 years as a player and a coach. He isn't about to change now.

It was his reputation as a no-nonsense disciplinarian that brought van der Hart here. After signing Gerd Mueller and Teofilo Cubillas before the 1979 season, Fort Lauderdale management thought it had a Soccer Bowl contender.

Meuller finished third in the NASL in scoring; Cubillas fifth. But the team was less than great, 17-13, and lost in the first round of the playoffs to the Chicago Sting. Exit Ron Newman, the winningest coach in NASL history, a polite, soft-spoken Englishman. Enter van der Hart, a blunt, burly Dutchman.

Van der Hart was an assistant coach on the Dutch national team led by John Cruyff, which finished second in the 1974 World Cup. He quickly jumped to Cruyff's defense today when the Dutch star's scoring statistics -- no goals, three assists -- were mentioned.

"You have to believe me when I tell you Johan is still the best player in the world," van der Hart said. "He will score goals. I don't know if he is getting the help he needs, even the great ones cannot do it alone. But he will score. Washington will win many games before this year is over?"

That English coach, Gordon Bradley, will have to find a way Saturday to stop a Striker attack that has been bolstered considerably by the addition of Ray Hudson (from Seattle) and Francisco Marinho (from Cosmos). The Strikers lost their opener in Memphis, then reeled off seven straight wins, including a 4-1 rout of the Cosmos, before losing to Seattle last week.

"Their talent is probably as good as almost any in the league," Bradley said.

Van der Hart is pleased with his team's record, but thinks the Strikers have a long way to go before they reach their potential.

Defender Bob Iarusci made the trip in spite of missing practice all week because of the neck injury which kept him out of last week's Portland game. He will start Saturday . . . Bradley said he will stick with beleaguered goalkeeper Bill Irwin at least.