Master Minded is likely to remain at the veterinary hospital in Newmarket for a month after having surgery on a leg injury.
Although the problem is not believed to be life-threatening, the racing career of the Paul Nicholls-trained eight-year-old may well be over.
The dual Queen Mother Champion Chase winner struck himself during the King George VI Chase at Kempton and was pulled up by jockey Daryl Jacob.
The Boxing Day showpiece was won for a historic fifth time by his stablemate Kauto Star. Both horses are owned by Clive Smith.
“It’s a very nasty injury. He had surgery last night. He struck into himself which means he cut into one of his tendons on his front leg,” Nicholls told Sky Sports News.
“Surgery went OK. It’s not a life-threatening injury, but it looks like it’s a career-threatening injury.
“He’s got to stay at the veterinary hospital in Newmarket for a month and fingers crossed he’ll make a full recovery.
“If he can’t race again he’ll have a fantastic home.”
Master Minded has won 16 of his 28 starts, including eight Grade One races, and amassed STG1,163,000 ($A1.81 million) in prize money.
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