A four-sentence deposition from Los Angeles Raiders owner Al Davis yesterday brought an end to testimony in the USFL-NFL antitrust case in New York.

Summations in the USFL's $1.69 billion suit, in which testimony began May 12, will be made today and the case will go to the five-woman, one-man jury Thursday.

In the deposition, the substance of which had been ruled inadmissible during Davis' earlier testimony, Davis said he had been told by Ralph Wilson, owner of the NFL Buffalo Bills, of dealings Wilson and Commissioner Pete Rozelle had with A. Alfred Taubman, owner of the USFL Michigan Panthers and then part-owner of the Oakland Invaders.

"I knew that the league had already talked to Mr. Taubman, by Mr. Wilson, an owner in our league, and by Pete Rozelle," Davis said. "Wilson told me that he had already informed this fellow that he would be an owner in the NFL."

One of the USFL's contentions in its case is that the NFL attempted to "co-opt" influential USFL owners . . .

Billy Sims, the most successful running back in Detroit Lions history, will retire today, team officials said. Sims, who hasn't played since suffering a knee injury midway through the 1984 season, has scheduled a news conference for this afternoon, when he is expected to end his five-year career, Bill Keenist, a spokesman for the team, confirmed . . .

With Jim Kelly all but guaranteed the job of starting quarterback for the USFL's New Jersey Generals, Doug Flutie says he would rather play another position than sit on the bench.

Flutie essentially became a second-stringer when the Houston Gamblers and Generals merged last summer. Kelly established himself as the USFL's No. 1 quarterback in two seasons with Houston.