When he was a child a very long time ago, Henry Clark often heard his grandmother talk about how his grandfather had bred and trained the winner of the Preakness in 1877.

Through his own career, Clark's greatest ambition has been to win this race, too. Now, at the age of 77, he finally has his chance. His colt Linkage will be the odds-on favorite to win the 107th running of the Preakness Saturday at 5:38 p.m. (WJLA-TV-7).

To reach this enviable position, Clark has had to endure an uncomfortable amount of controversy. Linkage's 5 1/2-length victory in the Blue Grass Stakes at Keeneland April 22 established him as the best 3-year-old in the country and the certain favorite for the Kentucky Derby.

When the trainer chose to skip the Derby and await the Preakness, he was widely criticized for snubbing a great American institution. He was also taking a risk, choosing to bring his colt into this race after a 23-day layoff while his principal opponents would have the important conditioning that the Derby provides.

But Clark has planned this route to the Preakness for months, and he has never wavered in his conviction that this is the way to prepare him for an optimal performance. "Since we've been back at Pimlico," he said this morning, "our horse couldn't have done any better. As far as I can tell, he's in perfect condition for tomorrow."

If he is ready to run his best race, Linkage will justifiably be a 4-to-5 favorite. His overall record--eight wins and two seconds in 10 career starts--is exemplary. His jockey, 50-year-old Bill Shoemaker, is a living legend. And the withdrawal today of the front-running filly, Cupecoy's Joy, should work to Linkage's advantage.

All the colts who tried to chase Cupecoy's Joy in the Derby collapsed in the stretch, and her presence in the Preakness had seemed to insure a fast pace. But her owners got mad and went home today when they didn't get as many seats as they wanted for the race.

The likelihood of a slow early pace will help the horses running on or near the lead--Linkage, Aloma's Ruler, Bold Style and Cut Away. It may hurt the confirmed stretch-runners--Laser Light, Reinvested and Water Bank--who finished 2-3-4 in the Derby.

Speed horses will have a further advantage if the track's condition Saturday is anything like it was today. Horses who managed to get to the lead on the rail virtually swept the card this afternoon.

In the absence of Derby winner Gato del Sol, whose trainer chose to skip the Preakness and await the Belmont, Linkage's principal opposition figures to come from Laser Light and Reinvested.

Laser Light was one of the most promising 2-year-olds in the country last season, but he was soundly beaten in his first three starts this season. Trainer Patrick Kelly offered a litany of excuses for these poor performances, but he didn't have to apologize for Laser Light's performance at Churchill Downs. Running ninth when the field turned into the stretch, Laser Light covered the last quarter mile in a sensational 23 4/5 seconds to be second.

Reinvested had never displayed any exceptional ability before the Derby, his principal victory having come in the Budweiser Derby at minor-league Tampa Bay Downs. But he made a powerful move entering the turn at Churchill Downs and finished third, a neck behind Laser Light. His half-mile workout in 46 3/5 seconds Thursday suggested that he is ready for another strong effort.

Aloma's Ruler also should get considerable support from the anticipated crowd of 80,000. Not only did he look impressive winning the Withers Stakes at Aqueduct last weekend, but he has considerable sentimental appeal, being owned by a Baltimorean (Nathan Scherr), trained by a regular on the Maryland circuit (John J. Lenzini Jr.) and ridden by a 16-year-old jockey. Jack Kaenel narrowly averted disaster when he was involved in an automobile crash earlier this week, and he will get the chance to become the youngest jockey ever to win the Preakness.

Nevertheless, the odds are that this won't happen. All signs indicate that age and experience are going to triumph in this Preakness.