“The horse doesn’t know what its odds are” is a horse racing adage of unknown authorship. “A horse doesn’t know what the odds are” was said in 1971 by a fan called Harry The Horseplayer. “The horse doesn’t know the price” was said in 1978 by American Hall of Fame thoroughbred racehorse trainer Laz Barrera (1924-1991). “The horse doesn’t know what his odds are” was said in 2005 by horse breeder Jerry Moss.
 
   
13 August 1971, Winnipeg (Manitoba) Free Press, “Meet Harry…The Horseplayer” by Dave Distel (TPNS), pg. 24, col. 4:
“A horse doesn’t know what the odds are,” he (Harry The Horseplayer—ed.) said.
 
18 May 1978, Aberdeen (SD) American News, “Affirmed is favored this time,” pg. 13, col. 2:
BALTIMORE (AP)—Trainer Laz Barrera, who felt it was a knock against Affirmed when the colt wasn’t favored for the Kentucky Derby, says: “I’d like to be 10-1 for the Preakness. The horse doesn’t know the price.”
 
Google Books
Style: Laughing through the Turmoil:
A Collection of Wicked Wit, 1980-1990
By Julian Askin
Johannesburg: CTP Ltd.
1990
Pg. 46:
“He’s all the way back to eight to one!” I moaned.
 
“Patrick,” said my bookmaker, “the horse doesn’t know what price it is.”
 
OZmium Sports Betting and Horse Racing Forums
grasscutter
2nd June 2002 08:15 PM
Contrary to popular belief that punters should follow the so-called “smart money”, results from saturday indicate otherwise.
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So forget about following this so-called “smart money” nonsense and back horses because they have the right ingredients to win. A horse doesn’t know what odds it is!!!!!
   
Thoroughbred-World.com
TRIPLE CROWN WATCH
Preakness post positions and M/L
May 19, 2005, 09:44
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JERRY MOSS (Owner of Giacomo): On the Odds of 6-1 for the Derby winner: “The horse doesn’t know what his odds are. We’re okay. Whatever happens, happens.”
     
Blood-Horse
17 October, 2008 5:52 PM
P.G. and a Horse Called Volponi
By Steve Haskin
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Then he heard track handicapper Mike Battaglia announce the colt’s odds at 50-1. “No way!” he said with indignation. When Mary Kay tried to act as the voice of reason by telling him the horse doesn’t know his odds, Johnson told her, “Don’t worry, at the three-sixteenths pole, you’re going to be proud of me.” Mary Kay replied, “I’m proud of you now.”
   
NBC Sports
May 2, 2014
ONLY AT THE DERBY: FAVORITE CALIFORNIA CHROME CAME FROM HUMBLE START
Just like the Run for Roses itself, budding 3-year-old has become an unlikely star
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To follow Steve Coburn’s line, the horse doesn’t know the odds.
 
A Sea Of Blue (University of Kentucky Wildcats)
The Kentucky Wildcats Win On The Road Over the Texas A&M Aggies 70-64 in Double-OT
By Glenn Logan  @ASeaOfBlue on Jan 10 2015, 4:35p
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The old saying is, the horse doesn’t know what it’s odds are, and I think that can be fairly said about Texas A&M today.