Sportscaster Howard Cosell contradicted his former boss today, testifying that ABC Sports chief Roone Arledge told him that NFL Commissioner Pete Rozelle "was all over me" for televising U.S. Football League games.

On a day full of bombastic, high-decibel testimony that often had the packed courtroom full of laughter, Cosell testified that during a 1984 lunch meeting, Arledge told him: "You have got to understand that Pete is all over me in that I'm sustaining the United States Football League with a spring contract."

Whether or not the National Football League exerted pressure on the three networks, in relationship to the USFL, is a central issue in the USFL's $1.5 billion antitrust suit against the NFL. In earlier testimony, Arledge denied such a statement to Cosell and denied that the NFL had exerted such pressure on ABC.

As the USFL's last witness in a trial that is expected to last another month, Cosell, 68, gave an extraordinarily colorful performance, spending nearly his first 40 minutes under questioning from USFL attorney Harvey Myerson describing his education and honors.

Cosell, now a sportscaster on ABC radio and a syndicated newspaper columnist, spoke in his staccato tone, using his buzz words ("I tell it like it is"). Judge Peter Leisure and the six jurors laughed several times during Cosell's nearly four hours on the stand.

Cosell made allusions to the hostage crisis in Iran, rock singer Michael Jackson's Victory Tour, the Reagan administration, former New York Jets owner "David A. (Sonny as in money) Werblin," two of his own books, the puppet show "Kukla, Fran and Ollie," former baseball player "No. 42, Jack Roosevelt Robinson," Coca-Cola's recent attempt to acquire Dr Pepper and an honor he received from the National Order of the Leather Helmet. He also testified that in the earliest part of his radio career, he went "from locker room to locker room with a 40-pound tape recorder on my back."

Under questioning from Myerson, Cosell made several accusations against the NFL and ABC:He said Arledge asked him to move up the date of his scheduled testimony before a Senate subcommittee that was considering a bill relating to franchise relocation. He did so, Cosell said, because Rozelle was "very disturbed" that, if Cosell didn't testify at an earlier date, the Senate might adjourn before the NFL had an opportunity to present its views on the bill.

Earlier, Arledge had testified that he made no such request but only cautioned Cosell that he was testifying too often.He contradicted testimony of Jim Spence, Arledge's former deputy, who had testified that ABC opposed the principle of competitive bidding among networks. The USFL has argued in this case that the NFL awarded rights to televise the Super Bowl to each of the three networks on a rotating basis -- without any competitive bidding on the game -- so as to "tie up" the networks.

Cosell testified that "the facts belie" Spence's statement, noting that ABC bid for rights to the Olympic Games and the Rose Bowl.He described the NFL's supplemental draft of USFL players in 1984 as "overtly antitrust" and said that Chuck Sullivan, executive vice president of the NFL's New England Patriots, agreed with Cosell's evaluation in a conversation with him. The supplemental draft awarded NFL teams the rights to rookies signed by the USFL in 1984 if they ever chose to change leagues.

Under cross-examination from Frank Rothman, Cosell testified that Donald Trump, owner of the USFL's New Jersey Generals, once offered him part ownership of his team, which Cosell did not accept.

The exchanges between Cosell and Rothman, Cosell's own former attorney, were full of sarcasm and one-upmanship. After one lengthy Cosell speech, Rothman shook his head and asked Cosell: "Is it my turn?"

Rothman asked Cosell if he "was one of the three great men of American television," along with Johnny Carson and Walter Cronkite.

"In terms of durability over the past 20 to 30 years, the record speaks for itself," Cosell said. When pressed further by Rothman, Cosell added: "I feel I'm a unique personality who . . . has had more impact upon sports broadcast in America than any person who has yet lived."Correspondent John Kennedy contributed to this report.