The racing game offers its players perpetual hope. Any time a better opens a virginal Daily Racing Form he can hope that he is about to discover the horse who will change his life.

Ten years ago I found the horse who changed mine. The circumstances of his victory were so dramatic that I still consider Dec. 9, 1970, my most memorable day on earth.

A week earlier I had been riding the Gray Line bus to Laurel and happened to glance at the past performances for Liberty Bell Race Track in Philadelphia. The record of an animal named Sun In Action practically jumped off the page at me.

At the time I was not a particularly sophisticated or successful handicapper, but one of the methods I believed in then pointed clearly toward Sun In Action. In the first start of his career the horse had rallied from 18 lengths behind and lost by only 12 lengths. In his second start he had trailed by only two lengths early in the race and lost by 11. This change of running styles I deemed highly significant.

Sun In Action was scratched from the race in which I discovered him, and I waited eagerly for his name to reappear in the entries. When he was entered in a cheap maiden claiming race at Liberty Bell, I did something I never had done before in my brief career as a horse-racing columnist.

I devoted an entire column in the Washington Daily News to Sun In Action, telling readers to "stop worrying about your Christmas money." This was "the betting opportunity of the year."

My Daily News colleague, George Solomon, drove me to Philadelphia that day, bearing some $200 for our friends who had been infected by my enthusiasm for the horse. I had cleaned out my own meager bank account and bet $200 for myself.

Sun In Action went to the post at 20 to 1 in the second race. He broke well, and raced in contention as the field went to the first turn. But then he started dropping back, and back and back. With a quarter of a mile to run, the horse was trailing by 14 lengths, and I murmured my apologies to Solomon. t

On the stretch turn, Sun In Action began to accelerate a bit. In midstretch he was moving faster, and looked as if he might even get up to finish second. In the final yards he was flying, and the leader, Birchcrest, was virtually staggering. Their noses hit the finish line almost simultaneously. My heart was pounding wildly as I waited for the results of the photo finish that would be worth the then-astronomical sum of $4,000 to me. t

The photo disclosed that Sun In Action had lost by approximately half an inch. But at the same time Birchcrest's number went up, the stewards were posting the INQUIRY sign and my jockey, Martin Fromin, was claiming foul against the winner. A few minutes later the tote board went blank and Sun In Action's number went up, paying $43.20 to win.

My hands shaking, I went to the cashier's window and collected more money than I had ever seen at one time. Then I went to a phone in the publicity office and made a reservation for that evening at the Rive Gauche. Then, since Solomon worried that I was on the verge of cardiac arrest, I belted down a couple shots of Jack Daniel's to steady my nerves.

The next day, the front page headline in the Daily News read: Andrew BEYER'S HORSE COMES IN. I was a minor celebrity. Friends were overjoyed. So were readers who had bet on the horse, and for years I kept running into them. (In 1975 I hopped into a cab, rode from downtonw to Georgetown and started to pay when the driver said, "No charge; I had Sun In Action.")

Sun In Action was the source of recognition and great ego gratification for a fledgling columnist, but the animal had a more profound impact on me as a horseplayer.

I had been playing the horses since I was 12 years old, but never with any sense of assurance that the game was beatable. At the time I did not know any successful professional bettors; I knew only the old canard: "All horseplayers die broke."

On that afternoon at Liberty Bell, I came home not only with $4,000 but also with the now-unshakable convictions that this game was beatable, that I was going to beat it, and that this goal was worth pursuing. And I was right.