Wherever Mike Gill runs his horses, he generates resentment, controversy, suspicion and fear.

The New Hampshire-based owner has operated a stable at Delaware Park for the last three years, claiming horses and winning races at a prodigious rate. He expanded into Maryland last year and became a dominant force there, too. This winter he launched an invasion of Gulfstream Park, where his performance has stunned the racing world. Gill's trainer, Mark Shuman, claims horses and appears in the winner's circle here virtually every day, making Gill the top race-winning owner in America.

His aggressive tactics have provoked hostility from rival owners and trainers, who know that any time they run a good claiming horse they might lose the animal to Gill. But the Gill saga is about to take a twist, because a racetrack evidently resents his methods and his success, too. Delaware Park is expected to deny the owner stalls for its 2003 season.

"Last year I was told, 'Don't apply for stalls,' " Shuman said. "They said we claim too many horses."

Gill believes that Delaware's management is siding with the trainers who dislike and fear him. "It's the old-boy network," he said. "Sam Abbey [Delaware's racing secretary] screamed at Mark and told him, 'You're not coming back here!' "

Abbey, who was visiting Gulfstream this week, said: "I don't have any comment on Mike Gill. I didn't tell him not to bring his horses back. He can turn in his stall application." After observing Abbey's tight-lipped demeanor, I'll lay 50 to 1 that Gill's horses won't be in residence in Stanton, Del.

The fracas at Delaware underscores the intense passions involved in the claiming game. Once the sport was played in a genteel fashion, and it was considered almost unseemly to claim another person's horse. But over the years, claiming-oriented trainers have become more and more aggressive, with bigger and bigger operations. In the 1970s Bud Delp, King Leatherbury and Dick Dutrow dominated the game in Maryland. More recently, Scott Lake and Dale Capuano have played the game on a level that makes the erstwhile Big Three look like a small fry. Now Gill and his various trainers have become the most formidable players of all. "Michael has taken the game to another level," said Lou Raffetto Jr., chief operation officer of Laurel Park. "The trainers who used to be the big fish are now part of the food chain."

In a claiming race, any owner can claim any other owner's horse. Gill takes horses, Gill loses horses. "Last week," he said, "I ran five horses in a row and lost them all. That's the business." But the claiming game is a lot like a poker game, because the player with the biggest stack of chips has a distinct tactical and psychological edge. If Gill owns a horse worth $20,000 he might run him for $15,000 so he can dominate a race; if he loses the horse, he'll shrug. But a small-scale trainer will be less inclined to risk losing a good horse. Indeed, he is more likely to run a $15,000 animal for a $20,000 price tag because he fears he will lose him to Gill.

The main concern at Delaware is that Gill takes so many horses in certain categories that he dominates those classes totally. Trainer Allen Iwinski, a rival of Gill at both Delaware and Gulfstream, said, "A person who claims as many horses as he does unbalances the apple cart. If there are seven horses who might run in a $50,000 claiming race, but he has three or four of them, then the race doesn't go."

Gill responds that he is as conscious of this issue as anybody else; if a $50,000 claiming race doesn't materialize, he is hurt more than anyone. He believes that the real issue is that Delaware's management is siding with the trainers who have gone from being big fish to part of the food chain. He said he was at the track on a day that a $50,000 claiming race was being run, and trainer Michael Pino, a Delaware regular, had a good horse in the field. Gill recalled: "Sam Abbey told me, 'If you claim [Pino's horse] you're out of here!' "

Abbey's response: "He's a liar."

Delaware has the right to deny stalls to Gill; the assignment of stall spaces is an arbitrary business, and no owner or trainer has any special claim on them. Gill isn't barred from racing his horses at Delaware; he can ship them from Maryland, but the lack of stalls would significantly cramp his style.

Maryland's Raffetto is a former racing secretary and he understands both sides of this issue -- that an owner helps a track by filling its races but can hurt it by dominating a category too much. Of Delaware's position he said, "They have their proprietary rights. If there were questions about an owner's or trainer's integrity, I could deny them stalls. But if the issue is just that they are claiming too many horses, I'd have trouble doing that."

Questions of integrity are relevant in Gill's case. The owner was barred from the sport for three years by New Hampshire officials because of a drug violation. Most of his trainers -- including Shuman -- have been suspended for the use of illegal medications on their horses. Gill's veterinarian has a scandalous past. At a time when the sport is ultra-sensitive about public perceptions of its honesty, a racetrack might have a reasonable position if it denied the owner stalls because of these concerns.

But to oust him because of his claiming practices is absurd and unfair, and Delaware's intended actions do smack of an attempt to protect the old-boy network of trainers from a disliked outsider. The very nature of the claiming game has always demanded boldness and aggressiveness. How can a track reasonably get rid of an owner because he is too bold and too aggressive, playing the game better than anybody else?