When the movies venture into the horse racing for source material the production rarely figures to do better than show. A few films earn a place position. One of 50 is a winner.

So, last weekend, when Hollywood went Hialeah, horsemen here shuddered.

Metro-Goldwyn-Mayer sent its film crews here Thursday, Friday, and Saturday, to shoot background and title scenes for a remake of "The Champ," a 1931 classic that won an Oscar for Wallace Beery and marked Jackie Cooper's first screen appearance.

Knowing Hollywood's history with race track stories, I had intended to scratch from last week's prodeedings . . . until someone mentioned that Franco Zeffirelli was directing, which meant this definitely was not a claiming company. Zeffirelli has directed "Romeo and Juliet" and "The Taming of the Shrew" and has compiled a set of past performances equal to Seattle Slew's.

This is his first film in the United States. He is switching from Shakespeare to the shedrows, and he appears to be enjoying the sharp change of pace.

"You ask me why 'The Champ' and racing should be my selection for a movie and that's a very serious question. I'd have to tell you my life story," the Italian director remarked. "I saw the original when I was a child in Florence. My mother had recently died and my father remarried. I was very affected by the strong love between the father and the son in the movie. I cried for months. They almost wanted to send me to a doctor to see what was wrong."

Zeffirelli continued: "I recovered, naturally, then, for about 46 years I never thought about it until a year ago, I was in London. I had spent 14 hours in the cutting room that day. When I came back to my hotel I switched on the television - and there it was. All the emotions came back. I cried again. Then I called my agent. MGM had told me they would like for me to do a film, in America. Three o'clock the next morning they called back. We had an agreement."

Zeffirelli knows his way around the race track and race horses.

"This, again, brings me back to my childhood. My uncle was a great horse owner in Florence. I spent many of my happiest hours as a child in the stables, and following the horses. During those years, yes, I met Tesio, and I saw Ribot run, several times. One remembered both the man and the horse."

FedericoTesio is to thoroughbred breeding what Federico Fellini is to movie makers. He was way ahead of his time, theorizing brilliantly as to how to breed the ultimate race horse, then applying those theories to produce Ribot, quite possibly the greatest thoroughbred of modern time.

Perhaps, with Zeffirelli's background, "The Champ" has a chance to be successful.

"There have been many great movies involving racing," he said. "There was "A Day at the Races" with the Marx brothers. And there was Saratoga' with Jean Harlow, the last film she did.

"Racing is very much in the air now for film. "International Velvet" is being made as a sequel to "National Velvet" and Martin Ritt has just finished a movie about quarter-horses ("Casey's Shadow," starring Walter Mathau)."

MGM describes "The (1978) Champ" as a story featuring a former champion fighter, now working as a stable-hand at the racetracks, who is an ineveterate gambler. He wins enough, one day, to buy a horse for his 1-year-old son. He eventually loses the horse by gambling, but regains the faith of his son, who idolizes him. He fights, wins, but dies.

Zeffirelli obviously has his work cut out if he is to rescue this story line.

"The script is very difficult to adapt to our times, and preserve at the same time," he acknowledged. "Many thinks have changed since 1931. Women, especially. In the original film the woman never existed. Now we have to create such a character, and also to rejuvenate the beery character."

One important scene is already complete.

"That's where the boy sees the horse his father has given him fall, just short of the finish, just as he is about to win a race," Zeffirelli said. "The poor child goes through the worst hell of his life. That is a separate scene."

A youngster named Ricky Schroeder was acting out the long shot last week. The leading man's identity was still unknown, although Robert Redford and John Voight were mentioned as being interested. Zeffirelli reportedly had difficulty with Ryan O'Neal, who was originally set for Beery's role.

"That's very delicate; very delicate," Zeffirelli said. "I have worked with Bancroft, steiger,Oliver, Mason, Taylor and Burton, Callas, Magnani. I have had quite a gallery. Still, I think it is much more fun to work with an unknown, as I have in the past, for a picture like this. It has to be a man who is 36, 37, 38, Muhammad Ali's age, a man on the way down, without all the flesh on the hips Beery had."