Perhaps never in the history of the National Football League has one gangly 21-year-old quarterback with only 25 games of college experience caused so much confusion without playing a game.

The case of Bernie Kosar, the University of Miami quarterback who last month declared himself eligible for the April 30 NFL draft, has taken several swift and sharp turns in the last week, and today rests in the Park Avenue office of Commissioner Pete Rozelle.

Rozelle will listen to representatives of the Cleveland Browns, Minnesota Vikings, Houston Oilers, and Buffalo Bills tell how they got involved in Kosargate, and why. He also is expected to hear how two of these teams, the Browns and the Vikings, traded for him within hours of each other, precipitating a tug of war with the Browns and Bills on one side, the Vikings and Oilers on the other.

The Vikings traded their first- (third overall) and second-round picks to the Oilers for their first-round pick in the draft, the second pick overall. Because the Bills, who will draft first, already have signed Virginia Tech's Bruce Smith, they thought they were out of this. They're not, but more on that in a minute.

With this pick, the Vikings were going to choose Kosar, a junior-to-be in football who is eligible for the draft only because he can graduate this summer. But this is where the Browns, the team Kosar says he would like to play for, enter the picture.

The Browns traded with the Bills for the rights to the first pick in the supplemental draft, if there is one. The NFL holds such a draft in special circumstances; i.e., when Dave Wilson, the University of Illinois quarterback, was ruled ineligible for college play after the NFL draft in 1981. He was picked by New Orleans in a supplemental draft that year.

Art Modell, the Browns' owner, said he was "just covering" all his possible options with the trade.

Mike Lynn, the Vikings' general manager, said, "It smells terrible."

If Kosar must be a part of the April 30 draft, he almost certainly will become a Viking. If he waits out the draft and goes in a supplemental draft, he probably goes to Cleveland.

Does he have a choice? The Browns say yes. The Vikings, naturally, say no. The league, apparently siding with the Browns, told Kosar in a letter last week that he would have to notify the league in writing by April 15 whether or not he wanted to be eligible for the draft, and that he could be in a supplemental draft later if he wanted. He gets a choice, according to this interpretation, because he still has college eligibility remaining.

Kosar did not send the letter yesterday, although insiders say the April 15 date might not matter now that Rozelle has become involved.

The Vikings, interpreting league rules concerning college eligibility differently, said Kosar is eligible for the draft because he lost any remaining college eligibility when he obtained an agent, dentist John Geletka.

Who's right? Who knows? The NCAA will rule on the matter only if Kosar wants to go back to Miami, a spokesman said. The Hurricanes are practicing without him and do not expect him to return.

So the matter rests with Rozelle. The meeting is today. He said he will announce his decision by April 23.

It might take him all week to sort this out.