Running in the Belmont Stakes could be a bad mistake for a horse like Coastal, winner of his only three races this year, the last by 13 lengths in the Peter Pan.

David A. Whiteley, an ace trainer, has been agonizing over whether to run his promising colt Saturday with only three races under his saddle belt, none around two turns. Owner William Haggin Perry, a solvent man, will have to put up $20,000. Then there is Spectacular Bid, winner of 12 straight stakes races, including daylight wins in the Kentucky Derby and Preakness Stakes.

Yet, despite these obstacles, Coastal is expected to be sent to the post in the 1 1/2-mile classic.

That would be a mistake.

It is true that the arguments in favor of the son of Majestic Prince accepting the issue are persuasive.

The lion's share of the $273,000 purse is nothing to sneeze at. And the fact that the chestnut is likely to get at least a share of the purse enhance his prosspects as a sire.

Too, there is the possibility that Spectacular Bid, a slow breaker in his races of late, could get into trouble in the scramble for position around the first turn. All of these are valid reasons for Coastal's running Saturday.

However, experience shows that performers in any truly competitive sport must be seasoned for the tasks they are asked to do.

It is remembered that Alydar made his debut in a stakes race and that superior performer has never seemed to put it all together, despite a wealth of natural ability.

In boxing it is remembered that a young Ike Williams was battered late in his fight with champion Bob Montgomery before he was really ready for such a bout. True, Williams went on to become a champion, but he never achieved the greatness his natural ability promised.

The Belmont would appear to be a battle for the minor shares of the race, since form suggests it will be two-horse event. And the better Coastal runs the worse it could be for him in the long run. The lure of fame and fortune are traps his owner and trainer should avoid at this time.