"Casey's Shadow" is a beautiful title and a surprisingly appealing and stirring movie.

The first in a new cycle of horseracing melodramas, a genre Hollywood has suddenly rediscovered, "Casey's Shadow" sets a deceptively leisurely pace while establishing a genuinely involving dramatic conflict within the family of an obscure Cajun trainer, played by Walter Matthau, determined to seize his one chance at competitive fame and fortune.

Martin Ritt has never been an excitable director, and one could complain that he lingers over settings and local color or neglects to squeeze every ounce of conventional suspense out of the climactic big race, the All-American Futurity, which is held each Labor Dsy weekend in Ruidoso, N.M.

But who's complaining? There is to be gained from the Louisana and New Mexico locations, the datails of ranch life track procedure, character traits and relationships observed for their own sake, and the beauty of horseflesh.

"Casey's Shadow" is as firmly, pleasurably located as such earlier Ritt productions as "The Long Hot Summer," "Hudd" and "Sounder." The performers have an opportunity to merge woth the settings that is fre-(See CASEY, B2, Col. 1)(CASEY, From B1)quently sacrified when filmmakers rush, rush, rush to generate the trumped-up climaxes sometimes confused with dramatic action, especially on TV.

Moreover, the conventional elements of suspense that surround the big race are intensified by an ingenious, emotionally wrenching twist.

Matthau's character, named Lloyd Bourdelle, risks permanent injury to his once-in-a-lifetime colt, Casey's Shadow, running him in the big race, since the animal has pulled up lame after winning a qualifying heat. This calculated risk could also cost him the respect of his three feisty, independent-minded but habitually loyal sons - Buddy, an aspiring trainer in his early 20s; teen-age Randy, woh rides Casey's Shadow; and little Casey, who has been devoted to the Colt since it was born.

Bourdelle stands to lose a lot if he insists on gratifying his desire to win the big one. Moreover, he realizes that he feels irresistibly impelled to violate principles he's tried to impress on his kids. He holds a rival trainer played by Robert Webber in contrmpt partly because he considers him insensitive to the welfare of the animals in his care. But when Bourdelle, a struggling, nickel-and-dime operator, gets his first chance at reflected glory, he can't resist the temptation to take risks that he ordinarily considers unacceptable.

Obviously, there is more at stake in this story than a horse race. The extra emotional and ethlical dimensions give the movie much of its distinction and abiding human interest. Judging from the crude and facetious advertising campaign, Columbia is either oblivious to these dramatic virtues or afraid to acknowledge them. Some of the ads lead one to expect a revival of "Francis the Talking Mule."

This apparent inhibition may stem from an earlier version of the film, in which the story concluded with what might be regarded as an uncompromising ending - the destruction of Cavastating, was shot after preview audiences seemed too distressed by the original one.

This form of compromise seems justifiable. It doesn't take the characters off the hook or violate the value system the filmmakers desire to uphold. As American movies go, "Casey's Shadow" remains exceptionally tough-minded, as well as authentic, humorous and entertaining.

The movie is not a poor relation within the Columbia family. It's a Ray Stark production, and anyone who has followed the stories about David Begelman, the erstwhile president of the company, should know that Stark is an extremely influential member of the family. If he weren't, he might not have been able to shoot an alternate ending.

I haven't the slightest idea whether Matthau is a convincing Cajun, but his performance is amusing from the opening flourish, when he rouses himself from bed with his back to the camera and greets the day with a medley of groans, moans and coughs. This role proves at once a strong and entertaining variation on his earlier cunning slobs, personable scoundrels and flawed but unhypocritical father figures.

The rapport he achieved with the kids in "The Bad News Bears" carries over to his work with the young actors cast as his motherless brood in "Casey's Shadow." They constitute an unusually convincing family group, bound by both an ongoing set of personality conflicts and as ongoing sense of loyalty. The Bourdelles appear certain to inspire a television spinoff, in part because they're such an obvious improvement on the format of "My Three Sons."

As eldest son, a swarthy lean-visaged, bright-eyed young actor named Andrew A. Rubin makes an unassuming but enormously attractive film debut. The contrast of his sane, easygoing Buddy with Matthau's devious, tempermental Lloyd is almost as satisfying as the Montgomery Clift-John Wayne opposition in "Red River." Rubin's ingratiating, informal style tends to clash with that absurdly formal name. Couldn't he drop the middle initial?

According to the plot of Carol Sobieski's admirable, tangy screenplay, Bourdelle's wife abandoned the family sometimes before the story begins, a move that's not hard to comprehend when you contemplate Bourdelle. On the other hand, she seems to have left behind a terrific set of sons. Rubin's Buddy, Stephan Burn's Randy and Michael Hershewe's dark-eyed Casey seem an exceptionally keen hardworking, desirable group of boys. Buddy, who appears to be shouldering most of the housekeeping burdens, must have derived his emotional stability from someone other than dad. Anyway, it seems a shame to lose contact with the boys, if not the old man.

Stark originated the project after reading a John McPhee story about Ruidoso. In selecting Sobieski, who was born and raised in the Southwest, to develop a script and Ritt to realize it, he has followed through astutely on his initial producer's hunch. Now that he's also got a swell movie on his hands, it would become him even more to tip off the ad department.