Tiz The Law, the Belmont and Travers Stakes winner, has been retired and will take up stud duties at Coolmore’s US arm, Ashford Stud.

The hugely popular Barclay Tagg-trained three-year-old was set to continue his career in 2021 and had next month's Pegasus World Cup as his first target of the year.

But his New York-based owners Sackatoga Stable announced on Wednesday he was being retired on veterinary advice.

In a tweet, the owners said: "We are saddened to say that Tiz The Law has been retired based on veterinary advice. We were very much looking forward to his 4yo campaign, but his long term health is paramount. We are beyond grateful for the time we had with him."

In a later tweet, Sackatoga revealed that an issue had been identified with Tiz The Law after training on Tuesday that was at risk of becoming "catastrophic" had he continued to race.

Speaking to the BloodHorse, Sackatoga founder Jack Knowlton said X-rays had revealed bone bruising. "Yesterday I got one of those calls I dread answering," he said. "It was a call from Barclay when I don't expect him to call me. It was bad news.

"You don't want to worry about a catastrophic injury that would have occurred if we continued to race him," Knowlton added. "We had a second opinion and they both said we could not continue to train and race him. There was no decision to make other than to retire him when you get a diagnosis like that."

Coolmore America, who had secured his services as a stallion after the Belmont, said he would take up stud duties at Ashford Stud in Kentucky for the 2021 season.

A son of Constitution, Tiz The Law is a New York-bred trained by Tagg, just like his Sackatoga predecessor Funny Cide, the 2003 Kentucky Derby winner.

He won four G1s, including both the Belmont and Travers Stakes, before being beaten into second by Authentic when odds-on favourite for the Kentucky Derby in September.

The pair clashed again in the Breeders' Cup Classic at Keeneland, where Tiz The Law finished outside the first three placings for the first time of a nine race career, trailing in sixth behind Authentic.

He had been in training at Tagg's barn at the Palm Meadows Training Center in Florida with the goal of contesting the Pegasus World Cup on January 23 at Gulfstream Park, where he won the G1 Florida Derby in March.