Reigning United States horse of the year Wise Dan has undergone emergency surgery for colic in Lexington, Kentucky.

Wise Dan has won 10 Grade One races including two Breeders' Cup Miles and took out the the Turf Mile on the Kentucky Derby undercard earlier this month.

Trainer Charles LoPresti said the seven-year-old was uncomfortable after a routine gallop on Friday and was taken to the equine hospital where he underwent the surgery to repair a twist in his small intestine.

LoPresti, who accompanied his champion to the clinic, confirmed to the Daily Racing Form that Wise Dan was resting in recovery and expected to remain at the hospital for a few days.

Barring complications, Wise Dan could resume light training later in six to eight weeks.

Wise Dan was named Horse of the Year, champion older male, and champion turf male for both 2012 and 2013.