Sports and the courts have been a daily double of sorts in recent years. Thoroughbred racing has had its share of legal hassles concerning the "absolute insuror" rule applied to trainers, and over the rights of jockeys.

The most important case, however, so far as the nation's bettors are concerned, occured here in Washington in 1972, in tax court, when William H. Green, a taxi driver, attempted to show that his gambling losses for the season were at least as high as his winnings. If he had been successful, Green would have received a refund of money withheld from his winnings by the Internal Revenue Service.

Green resided in Washington at the time his petition was filed. He had filed an income tax return for 1966 with the district director of Internal Revenue in Baltimore.

During 1966, Green frequented Bowie, Pimlico and Shenandoah Downs. On at least one occasion, he acknowledged attending Aqueduct in New York. Green said he went to the races two or three times a week, occasionally going to the Maryland tracks in the afternoon and to the nearby West Virginia tracks at night.

Green admitted he occasionally bet on as many as three of four horses in a race in an attempt ot increase his chances of winning. However, he did not consider himself to have any winnings unless his winnings on a particular day exceeded his losses. He placed most of his bets himself, Green said, although occasionally having some bets made for him by friends.

On April 5, 1966, Green hit the twin double at Shenandoah Downs. The payoff was $21,854. Green signed IRS forms 1099, in receipt of the money, and reported this amount on his 1966 income tax return as his only gambling winnings. Aganinst this amount, he claimed gambling losses of $21,840. To support this claim, he submitted $23,680 in losing tickets, all allegedly purchased by him or on his behalf between April 6, 1966, and May 21, 1966. For the most part, Green did not keep a record of his winnings or his losses.

Unfortunately, several of the losing had been picked up from the floor of tickets Green presented bore what the judge called "unmistakable" heel marks. The inference was clear. They the grandstand, just as race track "stoopers" od everyday.

"As we noted in our findings, some of the losing tickets purportedly bought by the petitioner or on his behalf bore heel marks," the judge noted. "Other tickets purchased on the same day and at the same track are relatively clean. Petitioner, who was the only witness on his own behalf, failed to offer a satisfactory explanation for this circumstance.

"Petitioner went to the races regularly and frequently," the court continued. "He admitted that he often bet on several horses in a single race, yet he made no attempt to keep a record of his winning tickets. His explanation was that, except for the time that he won the daily double (the judge meant twin double) involved in this case, he never had a 'winning' day. We are unable to accept this bare, generalized assertion.

"Thus, even if we were to find that petitioner actually purchased all of the tickets submitted into evidence, we cannot find that he did not have other net winnings, beyond the daily double involved herein, which he failed to report."

That was a fair ruling. It bids to become particularly important this year, as a precedent, what with the Treasury Department about ready, with Congress' help to collect 20 per cent federal withholding on betting payoffs greater that $1,000 on bets won at odds of 300 to 1 or more. This will mean that a bettor who strikes it rich for $1,000 in the triple will receive only $800 at the cashier's window. Uncle Sam plans to get his cut immediately.

If the bettor's tax bracket at the time he files his income tax return is lower than 20 per cent, he would be due a refund, should he file for that refund with the IRS. There has been a federal income tax, too, on net gambling winnings for some time.

Thus, it is about to become more important than ever that a bettor seeking justice in a tax court keep excellent records in his day-to-day winnings and losings at the track. He should keep some sort of a journal, all his uncashed parimutuel tickets, and the daily program on which he has kept a record of his winnings or losings on each race.

Proving losses sustained in betting is tough, as the case of William H. Green vs. the commissioner, Docket No. 2495-70, T.C. Memor 1972-131, showed. But it could be worth the diffuculty. Just remember, tickets bearing heel marks don't figure to stand up very well in court as evidence. Losing tickets, long known as "dead soldiers," cannot be quite that dead.