Just after his arrival at the Tokyo Olympic Stadium to compete three years ago, Grewe was handed a letter by Masaki Kando. The volunteer confessed to being "very anxious" about his 13-year-old son Haruki having the amputation procedure, but learning about Grewe - a three-time world champion before the Tokyo Games - had inspired them, saying, "You gave great courage to my family. We are grateful to you."

Grewe commented on Instagram that the letter reminded him of his own battle with cancer eight years ago. He added, "I was scared, afraid to start my new life with a disability. Everything changed when I discovered the world of Paralympic sport.

"For the first time, I saw others who looked like me, competing on an international stage. My fears and anxieties were replaced with feelings of strength, potential, and ambition. Since then, it has been my goal to inspire the same passion for life into others, like Haruki, who may need a source of strength during their darkest days.

"You can take away the medals, the records, the money, the gear, the notoriety…if I can inspire just ONE person to continue fighting for their dreams, then it’s all worth it."

While they had bought tickets to watch Grewe in action, the ban on spectators from Tokyo 2020 venues meant Haruki and his family had to watch his hero on television. Grewe went on to the win Paralympic gold in the Japanese capital.

Three years later, with Kobe staging the 2024 Para Athletics World Championships, Kando found Grewe to pass him another letter with an update on Haruki who is now 16 and "currently obsessed with amputee football".

It concludes, "You and my son are already heroes. I want my son to grow up to be a hero like you, to others when they are in trouble. We are always grateful to you. Good luck."

After taking time out to focus on studying medicine at the University of Michigan, Grewe returned to competition after a gap of three years in March. He took second in the high jump T63 at the U.S. Paralympics Track and Field National Championships in Walnut, California behind reigning world champion Ezra Frech.

In Kobe on Tuesday, Grewe jumped a season's best 1.82m to take bronze. Frech was second with 1.85m as India's Mariyappan Thangavelu - who beat Grewe to gold at Rio 2016 before the American reversed placings in Tokyo - came out on top with 1.88m.

While still only 25, Grewe can now look forward to defending his Paralympic title in Paris with Haruki's story a source of continued inspiration and affirmation. As he says, "Win or lose, this is still what it's all about."