It began the way everyone at Georgetown had imagined. Before he had been on the court for one minute in his unofficial debut as a Hoya, Patrick Ewing sent a calling card to the college basketball world. The message on the card was clear: "I have arrived."

It came with 15:50 left in the first half of the Hoyas' 78-64 exhibition victory over Cibona of Yugoslavia last night before 2,718 in McDonough Gym. Ewing had not started because Coach John Thompson decided he wanted the 7-foot freshman to do as much blending in as the most highly publicized freshman in the country can do.

But with 16:23 left in the first half, Thompson sent Ewing and fellow freshmen William Martin and Anthony Jones into the game to a great roar from the crowd, which had come to see the player it had heard so much about for nine months.

Within a minute, point guard Fred Brown found himself sliding downcourt with the dribble. He saw Ewing with a small opponent trying to drape himself on him.

"We'd worked on it in practice a lot," Brown said, "so I went for it."

Without looking at the basket or Ewing, Brown flipped a lob pass toward Ewing. It looked as if the pass were too high and would hit high on the backboard.

But before it got there, Ewing reached up with his right arm, almost caught the ball, but instead tapped it off the backboard and through the hoop. For a brief second there was silence because the shot was so stunning. Then, the place went crazy.

"No, it didn't surprise me," said Eric (Sleepy) Floyd, whose 21 points led the Hoyas. "I've seen it every day in practice for a month. It wasn't that big a deal."

In all, the entire evening wasn't that big a deal. Floyd was brilliant, keying the second-half spurt that turned a brief 35-33 Cibona lead into a 51-37 Georgetown lead in a four-minute span. Brown was solid, running the offense and looking more confident than a year ago. Jones and Martin had their moments, particularly Martin, who looks as if he will be a great rebounder.

But it was Ewing who drew the attention.

Although his first moment was brilliant, Ewing showed he is just a freshman before the night was over. Once, he tried to put the ball on the floor in traffic and fumbled it out of bounds.

And, perhaps ominously, there was the same flash of temper he had displayed in the Capital Classic all-star game in March. Then, he almost fought with 7-foot Greg Dreiling after an exchange of elbows.

Last night, he showed his temper twice. First, with 4:26 left and the game in hand, he became frustrated by the pushing and shoving of Rajko Gaspodnetic and responded with a shove of his own. Brown jumped in to play peacemaker, pushing his teammate away from the Yugoslav player.

Thompson came on court and spoke briefly to Ewing. "I just told him it's going to happen and he should stay calm."

Ewing tried. But a minute later -- when 6-4 Aleksandr Petrovic, his team's leading scorer with 17 points, bear-hugged Ewing -- the trouble started again. Ewing tried to get the officials' attention. It didn't work, so he tried a different tactic: an elbow that landed on Petrovic's head.

"You never want that to happen, but the kid was pushing and holding him and the referee wouldn't call the intentional foul," Thompson said. "At some point when you're held that long you start to think maybe the guy wants to fight you."

What Ewing thought about the whole thing only he knows for sure, because Thompson does not allow anyone to question his freshmen before Jan. 1. But Thompson did reveal that Ewing told him before the game, "I'm nervous."

"I told him, 'How do you think I feel?' " Thompson said.

Thompson felt pretty good when the evening was over.

The Hoyas were not bothered by playing against a team that had the words "Bonita Banana" across the front of their uniforms (Cibona is a food processing company), and the team played aggressively, although sloppily, most of the night.

Ewing, with four impressive dunks, including cappers at the end of each half, showed his ability without tipping his hand in too many ways. Thompson played everyone, shuffling his lineup constantly and playing minimal pressure defense to keep the game close.

He looked impeccable in his light brown suit. "Had it since high school," he said.

Like the old suit, Thompson's veteran players looked good last night. Mike Hancock had 14 points, Eric Smith had some fine moments defensively and Floyd, playing both ways, lived up to his all-America billing.

But it was the new player that everyone wanted to see. Ewing's statistics -- nine points, three rebounds and five blocked shots (Thompson particularly liked the blocked shots) in 22 minutes -- may not have been overwhelming, but they weren't supposed to be.

This was supposed to be a beginning. It was -- an impressive one.