Olympic champion Adam Peaty was reportedly injured after an "altercation" with fellow Great Britain swimmer Luke Greenbank.
The clash happened at a recent training session, according to British Swimming, the sport's national governing body.
"It was quickly and effectively resolved by the athletes involved and the staff present at the session," a spokesperson told Sky News.
The Sun newspaper reported the incident took place after Peaty, 28, made a comment about Greenbank's girlfriend, Anna Hopkin - who is also a swimmer for Team GB.
After the confrontation, a picture appeared on social media showing Peaty - a three-time Olympic gold medallist - with a gash near to his left eye.
It is understood Peaty did not require stitches.
Peaty's own representatives echoed British Swimming's statement, telling the media the altercation with Greenbank on Friday was "minor" and "resolved there and then between them".
Peaty and Greenbank swam together in the men's 4x100m medley at the 2020 Tokyo Olympics, taking silver.
He swam alongside Hopkin in the mixed 4×100m medley relay team, which won gold at the same games.
The Staffordshire-born swimmer also won an individual gold in the men's 100m breaststroke - an event he holds the world record time for - to retain the title after winning at the Rio Olympics four years earlier.
Peaty, who was awarded an OBE after his triumph in Tokyo, also holds the world record for the 50m breaststroke.
However, he pulled out of the British Championships earlier this year, citing mental health issues and saying he was "not enjoying the sport".
"I'm tired, I'm not myself, and I'm not enjoying the sport as I have done for the last decade," he said in an Instagram post at the time.
Peaty, who took part in Strictly Come Dancing in 2021, added at the time he was "hugely grateful" for support from his fellow swimmers as well as family and friends.
He also suffered a setback in 2022 after breaking his foot in a freak training accident but was able to recover and compete at the Commonwealth Games in Birmingham last summer.
A mixed event saw him finish fourth in the 100m breaststroke - his first defeat in the event in eight years - but he bounced back 48 hours later to win gold in the 50m distance.
Peaty intends to compete at the 2024 Olympic Games in Paris - where he will seek to win a third successive 100m breaststroke gold medal.
He told The Times earlier this year: "The physical preparation goes on, so my body will be ready to fight again when my heart and mind have caught up. I'll be ready when I need to be ready."