Horton, who won the men's 400 metres freestyle at the Rio Olympics, was alerted to the potential skin cancer by a fan.
Horton, who won the men's 400 metres freestyle at the Rio Olympics, was alerted to the potential skin cancer by a fan who saw it on television and emailed the Australian team swim doctor.
He posted a picture of himself on social media Friday with a bandage covering the area of his chest where he had the mole cut out, thanking the anonymous fan for their "very good call".
The swimmer, who became the target of online trolls this year after calling Chinese swimmer Sun Yang a "drug cheat", said he had 10 stitches but planned to be back training on Tuesday.
"It?s a bit less dramatic than some people made out," he told The Australian newspaper in comments published Monday.
"But it did have to come out because it could have developed into something, so it's a nice reminder to get your skin checked.
"I had noticed it changing but I hadn?t done anything about it. That guy telling the team doctor made me think that I should get it checked out," he added.
Australia has one of the highest rates of melanoma in the world, with more than 1,500 people dying from skin cancer every year.
Horton said he still intended to contest the Australian national short course championships in Brisbane from November 3-5, the newspaper reported.