Tobacco Road now extends through Eastern Europe and beyond Red Square. Or so it seemed to an American basketball addict en route to perhaps the most intriguing possibility in years: the Soviets losing back-to-back games on their home court.

The U.S.S.R. has been the UCLA of the East for as long as almost anyone can remember -- and an unheralded collection of Italians winning over the national team here Saturday night in the Olympics had the Mucscovite hoop world dizzy both with frustration and anticipation.

That world is larger than Americans might think. A trip on the subway and half-mile walk to the area tonight was not much different from a ride through Greensboro the night North Carolina plays Duke for the Atlantic Coast Conference championship.

Bystanders assumed no one with an Olympic badge draped around his neck would be going anywhere but to the game -- and every few feet somebody would shout the Soviet equivalent of "need two." On the steps leading out of the subway, a policeman seemed to be berating two men for engaging in the capitalist crime of scalping.

Nobody could get within 100 yards of the arena. a line of guards stood almost shoulder to shoulder checking for tickets or special credentials -- and dozens of luckless fans pleaded with anyone who seemed willing to exchange his seat for a few extra rubles.

Their senses were correct. It's a fact. You can throw out the record book when the Soviets and Yugoslavs get together.

Russian fans have an engaging way of expressing their emotions. A young translator, his hands clutched in excitement, is likely to almost hyper- ventilate and sigh: "Such a moment." Or to nudge a foreigner and remind him: "The competition is extremely keen,"

That it was. Even ACC wars do not always produce what Yugoslavia and the Soviets mustered tonight: A Soviet defender appeared to punch a Yugoslav in the face just as he released a jump shot: A Yugoslav later appeared to spit twice toward the Soviet bench: The game went into overtime, after fierce arguing and two clutch free throws at the end of regulation.

There was one astonishing moment: With 10 seconds left in regulation, there was a call critical to both teams. It went against the Soviets. Imagine that. In Moscow, with a gym full of whistling, jeering, stomping crazies and Lord knows who lurking on the sideline, two officials had the nerve not to give the Soviets the benefit of the doubt.

Jan Holmin, from Sweden, and Simon Mottaart, from Belgium, are courageous men. They kept control of what could have been an exceedingly ugly game. They had the nerve to foul out the 7-foot-4 Soviet center, Vladimir Tkachenko, just when he was beginning to dominate the game in the second half.

With 27 seconds left in regulation, with three players from each team out of the game on fouls and the survivors on the court sporting welts all over their bodies, Yugoslavia seemed to have the game won.

It had a four-point lead and Ratko Radovanovic at the free throw line with three shots to make two points.

The 50 or so Yugoslav fans were singing and waving flags high in the stands. Home-team fans were streaming down from their seats and toward exits. s

But Ratko missed his first shot. He missed his second shot. He did not get the ball past the front rim on each of his line-drive efforts -- and might not have if he stayed there until the Olympic flame is snuffed out Sunday.

The Soviets charged downcourt and scored. Then they stole the inbounds pass, Serguei Iovaisha grabbed it, drove toward the basket and sank a layup There was a whistle. A foul. A possible three-point play and a miracle victory.

Nyet.

The officials ruled Ovaisha was fouled before he shot. The basket did not count. The argument was heated. Dean and Lefty never went at it with Lou Bello any harder. In the end, Ovaisha sank the one-and-one four shots and both teams fumbled the ball in the last six seconds.

Overtime.

And the stream of fans who had left their seats returned, as though it all had been a film sequence and now the projector was being run in reverse.

They should have stayed away. It was all a Yugoslav tease, for in the five-minute overtime the Soviets quickly fell behind by four points and eventually lost by 10. They lost mainly because Yugoslav has two of the best amateur players in the world, Drazen Dalipagic and Mirza Delibasic.

If any assistant coach at any American basketball factory saw tonight's game, he would book the next flight to Belgrade. These fellows can play with anyone. But the Soviet coach saw a comspiracy.

"What we saw on the court to a great extent," Aleksander Gomelsky said through an interpreter, "was when we had a nine-point lead (in the second half) there were five cases (calls) and three of them went in favor of Yugoslavia."

No, he amended in a hurry, that was wrong. Out of the five calls, four of them went against the Soviets. "In my opinion," he added. He also said the presence of the Yugoslav who holds a commanding position in the International Basketball Federation probably intimidated the officials.

Clearly, Gomelsky learned his basketball at the feet of American wizards, though he uttered a totally un-American judgement: "I think it is the team that wins and the coach that loses."

There was an angry exchange with a Yugoslav writer.

To a question about the final seconds of regulation, Gomelsky said: "It should have been counted three points. Admit it. You saw it yourself." "

The writer then insisted the final five minutes showed the superiority of Yugoslavia.

"About the last five minutes." Gomelsky said, "I admit it. But only that."

"We have very high-class players." the Yugoslav coach, Ranko Zeravica, said. "That was the deciding factor."

The Olympic tournament has been going on for more than a week -- and all that can be said after tonight is that Yugoslavia probably will make the gold-medal game. With two losses, the Soviets also might, because the other contenders might not win regularly in the Southern Conference.

But the power in international basketball outside the U.S. seems to have shifted from the U.S.S.R. to Yugoslavia. As near as can be determined, the Yugoslavs followed their 1976 Olympic victory over the Soviets with successes in three or four collisions.

How greatly it has shifted will not be known by Soviet sprts fans who did not attend tonight's game. Because it was so keenly anticipated, the game was shown on television here -- but only until the end of regulation.

Then the producers cut to a news program. When that had finished, a grim-faced man appeared on the screen and ended the drama by saying: "The game is over. We lost."