For baseball fans, the only game in town lately has been Finley vs. Kuhn, a long and spirited rivalry whose final innings are about to be played in a Chicago court. And they will be played before an umpire who calls 'em as he sees 'em but who, as the trial began, cared little about the sport he may alter drastically.

"I am going to resist the temptation to open this trial by saying: 'Play Ball.'" Judge Franklin J. McGarr said in mid-December. Also, he said: "It's no mystery that I have not been a dedicated sports fan and I'm not presumed to know very much about baseball. But I don't regard this as a baseball case. It's a legal case, and the issues are law issues . . ."

And the case is more interesting than might be assumed, full of trivia dedicated fans might well have forgotten: even a pinch of sex. But no legal spitballs. To the dismay of many, McGarr refused to allow Charles O. Finley and Bowie Kuhn to serve up the special adjectives they reserve for each other, confining the case to whether the commissioner of baseball has the authority to overrule a transaction in conformance with the rules.

That essentially is what Kuhn did when he voided two sales Finely made just before the June 15 trading deadline: Joe Rudi and Rollie Fingers to Boston for $1 million each and Vida Blue to the Yankees for $1.5 million. Even though Finely broke no rules, Kuhn contends he had the power to take such action "in the best interest of baseball."

It's right there in Article 1, Section 2 of the Major League Agreement, obvious as a line drive to center, Kuhn insists: "The function of the commissioner shall be to investigate, either upon complaint or upon his own initiative, any acts, transactions or practices charged, alleged or suspected to be not in the best interest of the national game of baseball . . .

"To determine after investigation what preventative, remedial or punitive action is appropriate in the premises and to take such action, either against major leagues, major clubs or individuals, as the case may be."

So, Kuhns legal hitters declare, the issue is not whether Kuhn acted wisely by voiding the sales but simply whether he had the power to do it. And the burden of proof is on Finley, they claim as final briefs are being prepared, to show that the commissioner does not have this right.

Their key question: "Can you identify a single transaction in baseball history in which three star players, in which the contracts of three star players were assigned, for cash only, at the same time in the middle of a season to pennant-contending clubs?"

To help bolster the contention that Finley merely was continuing the long and accepted practice of selling players, his lawyers offered Kuhn's own words of July 27, 1972, in testimony before a House Judiciary Subcommittee:

"The commissioner is not given the right of consent on a contract transfer. These things are processed through our office, but unless there's some irregularity, our office would not intervene in a transfer." And the administrator of baseball. John H. Johnson, said he told Kuhn a day before he voided the sales: "I see no rule violations."

Throughout the nearly 2,000 pages of transcript, lawyers for both sides offered McGarr the truth, but not always the whole truth. And some fascinating bits of baseball lore.

For instance, in the first game of a morning-afternoon doubleheader on Memorial Day, 1922, Max Flack played right field for the Cubs and Cliff Heathcote played right field for the Cards. Then the players were traded for one another between game and Heathcote played right for the Cubs in the afternoon affair and Flack right for the Cards.

In fact, the trade was made while Flack was at home for lunch between games. When he innocently reported to the Cubs' clubhouse prior to the second game, he was informed: "You don't live here anymore. You're a Cardinal."

Apparently, players have been traded - for cash, other players or both - since King Kelly was sold by Chicago of the National League to Boston of the National League for $10,000 in 1988.

Finley's lawyers offered an economist to testify that the $1 million each for Rudi and Fingers and $1.5 million for Blue was not outrageous. Had the Senators sold Joe Cronin in 1976 instead of 1934, his value would have been $1,052,000 instead of $250,000, the economist said. The $700,000 Connie Mack got when he broke up his A's in the 1930s would have been worth $2,553,085.70 in 1976 - after taxes, he also testified.

Kuhn's position seems to be moving along well much of the time, it having been estiblished that he had - and used - authority to open the major-league camps last spring during negotiations with the players and several other instances not specifically referred to in the agreement he signed with the owners.

But one question gets to the heart of the matter: what would you have done if you had been in Finely's position just before the trading deadline, with seven unsigned, and potentially unsignable, players?

"That will be decided only twice," McGarr told Finley's lawyer at one point. "It was decided once by the commissioner. It will be decided again by me. So, the other opinions are not admissible on this."

I offer one, anyway. I offer that Finely ought to win this case because he seems to have tried to deal his players for other players until the last possible moment. Had he been interested only in money why did he not sell Reggie Jackson and Ken Holtzman instead of trading them before the season for Don Baylor, Mike Torrez and Paul Mitchell?

Still, those words in the major-league agreement, signed by Finley in 1964, although under porotest, weigh heavily in favor of Kuhn. Finely's lawyer may regret opting for a nonjury trial.

Oh, you were waiting for the sexy part. That was provided by historian Fred Lieb, who volunteered a story about taking the first commissioner, Judge Landis, to the Earl Carroll Vanities in the early '20s.

They were just beginning to get "a little daring" in the theater, Leib told the court, with "a nude who clung to the pendulum of a clock that swung back and forth, little merry-go-rounds and each had a single girl in it with her bare breast . . ."

Said McGarr: "You have gotten into the only area more interesting than baseball."