"When I go to the barn," Johnny Campo said the other day, "I have the blinkers on. I don't think about anything else; nothing bothers me. I just train my horses."

Ordinarily, Campo's comment would be an innocuous cliche. But as he prepares Kentucky Derby winner Pleasant Colony for Saturday's Travers Stakes at Saratoga, his concentration and competence are a major issue. For the last two weeks the trainer has found himself in the midst of controversy, intrigue and possible scandal.

Anyone who picked up the New York tabloids to read headlines such as CAMPO DENIES AFFAIR WITH DEAD VET could easily become unnerved. And Campo's horses have been performing dismally since the mysterious death of veterinarian Janice Runkle.

On July 27, the Monday before the Saratoga meeting opened, Campo drove Runkle from here to the Albany airport, where she had a reservation on a flight to New York. She didn't board the plane. Instead, using a false name, she bought a ticket to Chicago, where she apparently had no family or friends, and checked into a hotel there that night.

Four days later her body was found on a desolate Lake Michigan shore. An autopsy disclosed that she died of an overdose of a sedative called penobarbital. Before she died she had written letters to her sister, Diane Rameriez, and her friend, Newsweek columnist Pete Axthelm. Police in Lake County, Ill., who have been investigating Runkle's death, have declined to disclose the contents of those letters.

There was talk that John Campo was allegedly Runkle's lover, and that they had fought. The trainer, who is married and has two sons, denied this vehemently. Runkle, he said, was a protege and a friend of himself and his wife. But he would not have an easy time persuading members of the gossipy racetrack community of his noninvolvement.

The racetrack community also loves conspiracy theories, and it's easy to manufacture a hundred plots about the death of the vet of the horse who won the Kentucky Derby and Preakness and then was upset in the Belmont. Another factor contributing to the intrigue is that Runkle once worked for Dr. Mark Gerard, a New York veterinarian who was later convicted on two counts of fraud and spent eight months in jail for switching two horses at a Belmont Park race in September 1977.

Runkle's family continues to suspect foul play, and many questions remain about the events that preceded her death. The gossip and speculation isn't going to stop for a long time.

To a nonhorseplayer, the notion might seem preposterous that an animal's performance could somehow be affected by rumors about his trainer's life. But trainers can be as streaky as crapshooters. When things are going well or badly for them, the performance of every horse in their barn may seem to be affected.

Whatever the reason, Campo's horses have been running terribly here (In one stretch, 14 of 15 horses he saddled finished out of the money.). Now he is trying to perform a very difficult training feat with Pleasant Colony.

The colt has not started since he lost the Belmont Stakes 10 weeks ago. Campo decided not to run him in a prep race for the Travers, and instead is trying to prepare him for the 11/4-mile event with workouts alone.

Pleasant Colony has worked fast, just as he did this spring when Campo took over the colt and won the Wood Memorial Stakes after a layoff of several weeks. But everything broke right for Pleasant Colony on that day. On Saturday, he will be meeting a number of top horses -- Five Star Flight, Lord Avie, Noble Nashua -- whose trainers believe they are coming into the Travers in the best shape of their lives.

"The way those other guys are talking, I'll probably be off the board," Campo said. "I'll let these guys say what they want. I'll shut my mouth and speak after the race. Pleasant Colony is fit, perfectly sound and ready to run."

Campo has been uncharacteristically reticent since the tabloids started writing about the nature of his relationship with Runkle. But if he can shake off the distractions and pressure and win the Travers Saturday, he will probably be more communicative.