A genuine star has emerged from the ranks of America's Derby-age colts.

Undefeated Star Gallant provided evidence today that he may be a future champion, may in fact be another Seattle Slew, when he ran away from a field of outstanding 3-year-olds at Gulfstream Park.

He won the Fountain of Youth stakes by four lengths over Distinctive Pro, and did it in a manner that suggests his potential may be almost limitless.

Star Gallant has done wondrous things almost every time he has set foot on a race track, but enough doubts still surround him that he was only the third choice in the wagering today. Star Gallant looked as if he might be too fast for his own good and might not be able to go a distance because his speed was uncontrollable.

The same questions applied to the favorite, Distinctive Pro, and the jockeys on both horses were intensely concerned about what the other would do in the early stages of the race. So when the gate opened and Star Gallant broke very sharply, Sandy Hawley cast a quick glance inside to look at Jorge Velasquez on Distinctive Pro.

"I had thought Distinctive Pro would be out there by himself," Hawley said, "but when I saw Velasquez taking hold I thought I could get an easy lead going into the first turn. Around the turn I said, 'This is great!' "

Trainer Lenny Imperio was thinking the same thing, but he could barely speak. He has been the man under pressure this winter, trying to prepare this precocious animal to go a distance, and he said, "When they went into the first turn my heart was beating so hard it hurt. I like a horse to come off the pace and when I saw he was on top I could hardly stand it. But when I saw :24 I said, 'Beautiful.' "

Star Gallant had covered the first quarter mile in a slow 24 seconds, had taken a clear lead and dropped to the rail. Distinctive Pro was staying just outside him, within striking distance. "I knew I couldn't let him get too far in front," Velasquez said. "I had dead aim on the leader all the way."

As they reached the far turn, Distinctive Pro moved up on Star Gallant, and the longshot Cut Away moved into contention, too. But the leader pulled away from them. When they turned into the stretch, Distinctive Pro launched another challenge, this time his serious one. He had cut the leader's margin to slightly less than a length, when Hawley asked his horse to meet the challenge.

Star Gallant not only met it; he obliterated the challenger. He drew away steadily through the stretch, covering the 1 1/16 miles in 1:43 1/5. He paid $6.60 to win. Distinctive Pro finished 2 1/4 lengths in front of Cut Away, with D'Accord another length behind in fourth place.

Distinctive Pro's effort was quite a respectable one, for he proved that he is not a one-dimensional sprinter. "I was satisfied," trainer Jimmy Croll said. The disappointment of the race was D'Accord, one of the top-ranked 2-year-olds of last season. "I expected a response from him," disappointed jockey Darrel McHargue said, "but he never picked up the bit."

Both Distinctive Pro and D'Accord may take another shot at Star Gallant in the rich Florida Derby on April 4, but nothing that happened today suggests they could reverse the outcome. The only horse in Florida capable of beating Star Gallant appears to be Timely Writer, who is still rated as the favorite in the Kentucky Derby future-book wagering. The prospect of this confrontation does not daunt Imperio, nor should it. Star Gallant, he said, as he has been saying all winter, "is the best horse around."

Those still skeptical of Star Gallant will point out that the first quarter in :24 made things very easy for him, and that he still has not proved his distance-running capabilities in a hard duel. But the colt has raced only four times in his career, meeting every challenge, and will have the chance to prove many more things before this Triple Crown campaign is over.