A vet examination after a poor performance in the United Nations Stakes revealed that the Graham Motion-trained Main Sequence had suffered a tendon tear.

The 2014 Eclipse champion turf male and Eclipse champion older male finished seventh in the United Nations at his third start for the year.

Main Sequence, bred and raced by the Niarchos family, won nine times and placed six times out of 21 starts.

He retires with $3,428,666 in career earnings.

The 6-year-old flourished when he was transferred to Motion in 2014, winning four consecutive G1 races including the Breeders' Cup Turf.

Motion said the horse will be sent to his brother Alexander's Old Chapel Farm in VIrginia for rehabilitation.

He said the nature of his injury would not preclude him from a possible second career.

"It is an injury a horse can come back from. It is a matter of rest," he said.

"But the horse doesn't owe anyone anything, and the family would like to see him retire a champion.

“He would be capable of doing other things, but it is all to be decided."