According to Gun Runner’s trainer Steve Asmussen, the stray shoe was not immediately evident.“[I only noticed it] once he slowed down,” Asmussen told the New York Racing Association.

During the backstretch run, Cautious Giant sent a horseshoe flying. It stuck an unlikely landing as it caught itself in Gun Runner’s tail while they were still running.

“Can you believe that? I mean, if we tried to throw one and stick [it] in one’s tail as he was standing, still we’d go 0-for-1,000 — let alone at a run, let alone Gun Runner, let alone in the Whitney — and it stayed.”  

Gun Runner still won the race, ahead 5¼ lengths, the horseshoe visibly entangled in his tale as he crossed the finish line — his fourth U.S. victory in a row, second in Grade 1 competition.

“We were obviously unaware of it until he came back to the winner’s circle, but not a nick on him,” says Asmussen.

When he got to the winners’ circle, the shoe was detached and discarded. The horse’s team realized the peculiarity of the situation and retrieved the shoe, forced to buy it back from a fan who had picked it up.

The shoe will serve as an artifact of a collection of unlikely circumstances. “My kids took it home,” says Asmussen. “They were going to put a shadow box around it.”