Updated 11/22/11 – 8:35 p.m.

PEOTONE, Ill. (CBS) — An owner believes someone tried to kill his racehorse last week to keep it from running for a $100,000 purse next month.

Talented Magician, a 3-year-old gelded quarterhorse, was fine Thursday evening when owner Ruben Flores left him in a barn in the 32500 block of South Center Road.

LISTEN: WBBM Newsradio’s Bernie Tafoya reports

Horse trainer Erica Rossi told CBS 2’s Mike Puccinelli that she spotted a lump the size of a grapefruit on the horse’s neck on Friday.

It was found on Talented Magician’s neck after the horse’s owner asked her to check on his animal for a swollen lymph node.

“It wasn’t a swollen lymph node, apparently. It was a needle mark,” said Rossi.

The veteran horse trainer said it was immediately clear to her that somebody had shot up the horse.

“It was a puncture wound … not like a spider bite or something normal,” Rossi said.

Will County Sheriff’s Department police agreed.

“We are trying to determine what kind of substance perhaps was injected in this horse,” said Will County Deputy Sheriff Ken Kaupas.

Flores said he thinks someone may be trying to sabotage his horse.

Rossi agreed and said she thinks she a jealous competitor might be behind the crime.

Perhaps that’s because Talented Magician had recently been on a hot streak placing in the top three in his last three races.

While the horse appeared to have plenty of pent up energy on Tuesday, it was acting a lot differently when Rossi first examined it Friday morning.

“It was a lot more calmer than it should have been, like, very out of it,” said Rossi. “Racehorses tend to be usually more hot-blooded, so they’re more excited.

Investigators are waiting on the results of blood tests.

Authorities expect they could have results back next week.

If Talented Magician sufficiently recovers, he will be loaded into a trailer and driven to Florida to take part in a race at the Hialeah Race Track, with $100,000 purse at stake.

Flores isn’t sure whether the gelding will be ready. He also said he fears the horse might have been doped with steroids in order to get it disqualified from the race.

Rossi said she isn’t sure what happened but is certain it was cruel.

“It’s disgusting. It’s not fair to the horse, despite these childish things between men and racing. It’s not fair to the horse. The horse didn’t ask for it,” she said.

Police said if it turns out that the horse was poisoned, the perpetrator could face federal and state charges if caught.

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