Australian international dressage rider Lyndal Oatley has paid tribute to her Olympic partner, Sandro Boy, who died suddenly on Friday aged 17.

The bay gelding (Sandro Hit x Argentinus), who last competed in November 2017, was at the end of a light stretching session at home in Appelhulsen, Germany, when he died of what is believed to be an aortic rupture.

He was in good spirits; super happy and being his usual self,” Lyndal told H&H. “He had finished his stretch — he is semi-retired but he likes to move. He came into walk and his hind legs became unstable. He looked at me and screamed; I ran to him as he never screams, and I got there as he went to the ground. He was gone within a minute.”

Although an aortic rupture is the most likely cause of death, Lyndal does not plan to find out for sure with an autopsy as “I want him to be in peace”.

“Utterly heartbroken and have no words,” the Olympic rider, who is married to Swedish international rider Patrik Kittel and is expecting their first child, wrote on Instagram.

Lyndal has partnered “Nissa” since 2012, competing at the World Cup final and the Aachen CDIO5* in 2016 and representing Australia at both the London Olympics in 2012, and the Rio Olympics in 2016 — the pair’s final international competition together.

“He changed my world. He taught me so much, made dreams come true and was my rock,” Lyndal wrote in a tribute to the gelding. “He died unexpectedly and quickly today while still making sure all around him were ok before very quickly leaving us.

“He had a cheeky sense of humour and gave me all the dreams a horse girl could ever ask for whilst still being his own person… and for that I loved him more! My world will be very empty without him and I can’t begin to imagine it without him.”

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