Millionaire businessman Allen R. Glick gave a chilling recitation in federal court here today of the life-and-death grip in which the Mafia held him in return for a loan from the Teamsters Union's Central State Pension Fund.

"I felt like someone who had just arrived on an alien planet," Glick said of his rude introduction in late 1974 to the realities of the Las Vegas casino business. "I was a businessman. I realized that I'd just entered into a trap."

The occasion, Glick testified at the casino-skimming trial of eight reputed mob leaders and their associates, was his attempt to fire Frank (Lefty) Rosenthal as the head of his "Nevada operations."

Glick, who had just bought the Stardust and Fremont casinos with a $62.75 million loan from the Teamsters, had given Rosenthal the job at the insistence of reputed Milwaukee mob boss Frank Balistrieri, who had arranged the loan for Glick. But Glick, then a 32-year-old whiz-kid businessman, said he soon discovered that Rosenthal had started hiring and firing people without Glick's approval and even had Glick's secretaries spy on him.

Glick said they had a confrontation in the Stardust Coffee Shop in October 1974. Rosenthal, a longtime representative of the Chicago mob in Las Vegas, "listened intently" to Glick's lecturing, left the table, then wheeled around at him.

" 'I think it's about time we had a discussion, Glick,' " Glick said he was told. " 'You're not my boss. And when I say you're not my boss, I'm talking not just from an administrative position, but from the position of your health. If you interfere with what's going on here, you will never leave this corporation alive . . . Test me.' "

Glick said he was stunned to learn so abruptly that he had acquired a set of "partners" whom Rosenthal did not name. He said he telephoned Balistrieri, who only confirmed that "what Mr. Rosenthal said was accurate."

Glick kept trying to curtail Rosenthal's activities until finally, one evening, he was called to the phone. It was Rosenthal demanding an immediate meeting.

Glick said he couldn't make it. Rosenthal told him, "with graphic threats and so forth," that he had no choice. Glick said he commandeered a corporate plane and flew to Kansas City that night. He said he was picked up by Rosenthal and a man "introduced to me as Carl DeLuna," for years the right-hand man and reputed enforcer for Kansas City crime boss Nick Civella.

DeLuna, 58, was a defendant in the case until yesterday, just before Glick began testifying. He reportedly agreed to plead guilty at a secret court session and was returned to Leavenworth federal prison, where he is presently serving 30 years in another skimming case.

On the drive to a nearby hotel, Glick said he was told he was about to meet Nick Civella, "a very powerful individual who was much more prominent in his circles than Mr. Balistrieri."

With that, Glick said, he was escorted to a darkly lit hotel parlor with two chairs set up in the middle of the room, one with a light shining on it, "like interrogating a prisoner in a police room."

Glick said Civella appeared and told him "in a cold, calculating way . . . that I should cling to every word he said. He said, 'You don't know me, but if it would be my choice, you wouldn't leave this room alive.' "

Civella, who died of cancer in 1983, emphasized that the Teamsters loan was "his doing" and that he couldn't believe Balistrieri had failed to tell Glick that. Glick said the only obligation he knew of was the hiring of Balistrieri's two sons as lawyers for his holding company, the Argent Corp. Their fees apparently totaled about $100,000 a year.

Annoyed, Civella replied, " 'You have a commitment to us. You owe us $1.2 million. I want that paid,' " Glick testified. He said Civella told him that " 'we' " also owned part of Argent.

When Glick protested that he couldn't come up with such a huge sum, he said Civella told him, " 'We will let Mr. Rosenthal handle that.' "

At that time, Glick had been counting on another $40 million in promised Teamsters loans to refurbish his casino-hotels, but Civella told him to forget about the money.

"He said he was going to personally see to it that I did not receive the additional funding," Glick testified. "To illustrate how much authority he had, he said those loans would be canceled." Finally, Glick recalled, "He said, 'Get out.' "

The next morning, back in Las Vegas, Glick said he sought out Rosenthal to tell him, "I wasn't willing to live under these circumstances."

Rosenthal, Glick related, told him, " 'You are no longer in a position where you control your destiny with this company.' "

Prosecutor David B.B. Helfrey asked Glick, who sold out his casino interest in 1979, whether he ever received another loan from the pension fund. "No, I did not," Glick said.