The past performances of Sensitive Prince are impeccable: five starts, five victories, a record strong enough to make him the third choice in the future book for the Kentucky Derby.

The bay 3-year-old colt is of splendid parentage, having been sired by 1969 Derby winner Majestic Prince out of Sensitive Lady. a Sensitivo mare.

Sensitive Prince was quartered last summer on Dr. Mark Gerard's farm near Muttontown, N.Y. Gerard, a veterinarian, is the central figure in the alleged switching of horses before a Sept. 23 race at Belmont Park. He was indicted by a Nassau County grand jury last December.

It has been charged that Gerard killed the late, not-so-great Lebon and substituted a superior horse with similar markings, Cinzano, which ran as Lebon and won a race at 57-to-1 odds. One better, Gerard, collected $77,920 on the horse.

Gerard sold what was thought to be Cinzano (the horse that died) for =150,000 to Joseph Taub, owner of Derby candidate Sensitive Prince, before the controversial race.

"I have nothing to hide. Mark Gerard and I have had a long relationship," Taub said yesterday from his home in Tenafly, N.J. "I called in Dr. Gerard to look at this horse (Sensitive Prince) in Florida last spring, at Golfstream park, after he had broken a track record in his first race at Hialeah.

"Sensitive Prince had sore shins," Tayb continued. "He was going to buck (his shins). Gerard evenually recommended the horse should be stopped, taken out of traning. That's when we decided to take Herb (Paley the first trainer) had him, to Mutton-town, in June, so Gerard could continue to treat his shins."

Sensitive Prince made but one start as a 2-year-old. April 14 in Floride zipping five furlongs in .57 1/5 as the 17-to-10 favorite. The word was out early about this horse, as the odds reflected.

"He was special, even then," one trainer volunteered. "He was the kind that could fall down, get up, and still win."

But when Sensitive Prince made his first appearance in Florida this year, he had a new trainer.

""A lady, through an agent, offered to buy a half-interest," Taub explained. "There was one stipulation: that Allen Jerkens train the horse. I called Allen to come take a look. He liked what he saw. Then the lady reneged. She was told by her advisors she was paying a ridiculously high price for a horse that had run only once.

"But I'd already talked to Allen. I was inside sort of a buck. I felt committed. Allen was given the horse to train."

Sensitive Prince continued to run fast this winter, winning twice at Hialeah, equaling a track record in the Hutcheson Stakes on opening day at Gulfstream, then coming back to edge Believe It last week in the Fountain of Youth Stakes before being shipped to New York to prepare for the Kenucky Derby.

"I'd bought horses off Gerard before I bought the one he brought in from Uruggusy," Taub said. "All I knew was what I read in the paper. I short time later they sent me $137,000 short time later they sent me $1 7,000 in insurance (less the premium) for him.

"Now I'm waiting to see what happens. like everyone else. I think Gerard is the greatest vet in the world. He only handled the best, horses like Secretarist, Hoist The Flag, the very best.

"All I know is right now, with the interest on Sensitive Prince instead of the other house, I don't sleep because of going things that are happening," Taub said.

What puzzles some observers close to Sensitive Prince is how Gerard still pays as much attention to the colt as owner Taub.

Sensitive Prince was foaled in Maryland on April 1, 1975, at Dunmore Farm, north of Baltimore. And while Taub denies that Gerard, or anyone else, owns a piece of the horse some people think otherwise.

They believe Dr. Mark Gerard hascalled most of the shots with Sensitive Prince.