Many of the horses in the equestrian jumping course at the Olympics in Tokyo make a sharp turn going into the 10th obstacle and stop short of jumping. The popular theory is that the horses get scared by seeing the backside of a decorative yet realistic sumo wrestler statue positioned directly adjacent to the jump. The statue is in an attack position and the first thing horse and rider see are buttocks split by the mawashi a sumo wrestler traditionally wears.
"As you come around, you see a big guy's (butt)," British rider Harry Charles said.
"There's a lot to look at," Ireland's Cian O'Connor added.
"It is very realistic," echoed Israel's Teddy Vlock.
"I did notice four or five horses really taking a spook to that," Charles said.
A few of the pairings stopped short of the barrier, costing them valuable points to make the finals. Not all riders are blaming Mr. Sumo however.
Maybe," France's Penelope Leprevost said, "We tried to relax our horses in the turn, and maybe they're surprised to see a vertical so close. I don't know."
Of course, it's hard to know what's in a horse's head. Some riders chalked up the troubles to how close the jump was positioned to the turn. Others blamed the stadium's bright lights that also led to concern at jump No. 1.
Medal hopefuls Scott Brash of Britain and Martin Fuchs of Switzerland believed cherry blossoms positioned on the other side of the jump were the more likely culprit.
Whatever the cause, it's not surprising to Olympic veterans that there's drama around the park. The Games have a reputation among riders for flashy course design, including an oddly shaped jump at Rio de Janeiro in 2016 that caused similar consternation.
"To be honest, you expect it in the Olympic Games," Brash said.