Elijah Porter, 10, reached out to the men's 4x100-metre running relay team after it was disqualified when one of its members stepped out of bounds.
Porter, who lives in Paradise, near St. John's, wrote the team a letter saying they were good athletes and what happened to them was wrong.
"I decided that even though I can't change the rules I can make them feel better. So I decided to send my soccer medal and a note that started with talking about everything that's good about Canada," he told CBC.
It was his only medal.
"I'm not much of a sports boy but when I was younger I was doing a little soccer thing in Mount Pearl," said Porter.
On Monday, one of the Canadian sprinters, Justyn Warner, tweeted a photo of Porter’s letter. Since then, the story has caught fire on Twitter and Facebook.