AP McCoy's intended Scottish Grand National mount Benvolio has been declared a non-runner for Saturday's feature race.
The 19-times champion jockey was due to partner the eight-year-old in what would have been his final ride in the Ayr contest before he retires next weekend.
But trainer Paul Nicholls has taken Benvolio out because of the going.
McCoy, 40, finished fifth on Shutthefrontdoor in the Grand National.
"Sadly, Benvolio was really the only one I could do the weight on," McCoy explained to BBC Scotland.
"I didn't know how it was going to work out when I announced my retirement but the reception I've had everywhere has been very nice."
Champion trainer Nicholls is still represented by the top weight Sam Winner, ridden by Sam Twiston-Davies.
And Benvolio's place in a 30-strong field goes to first reserve, Sue Smith's Vintage Star.
Ante-post favourite for the race for some time has been Tony Martin's Gallant Oscar, who ran so well behind The Druids Nephew at Cheltenham.
He was bought by leading owner JP McManus this week, with Paul Carberry riding the nine-year-old for the first time.
Other major contenders include the Jonjo O'Neill trained-Catching On, David Pipe's Broadway Buffalo and last year's winner Al Co, trained by Peter Bowen.
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