Three-time Olympic champion Adam Peaty sustained a facial injury in a minor altercation with fellow Great Britain swimmer Luke Greenbank during a recent training session.
It is understood Peaty did not require stitches, with British Swimming saying the incident was "quickly and effectively resolved" by the athletes and staff present.
The Sun reported the incident took place after 28-year-old Peaty made a comment about Greenbank's girlfriend, GB swimmer Anna Hopkin.
However, Peaty later told The Times he had not mentioned Hopkin.
"Me and Luke are fine," he said. "We had a moment and then shook hands immediately after some tension after a hard training set.
"I have no idea how Anna got dragged into this. I didn't even mention Anna and it's unfair on her."
Peaty and Hopkin were part of the GB team who won 4×100m mixed medley relay gold at the Tokyo Olympics in 2021, while he and Greenbank helped GB to silver in the 4x100m medley.
Peaty - who holds the world record for the 50m and 100m breaststroke - pulled out of April's British Championships, citing mental health issues.
He has previously spoken about periods of depression and problems with alcohol, and earlier this year said he had been in a "self-destructive spiral".
He still intends to compete at next year's Olympic Games in Paris, where he will seek to win a third successive 100m breaststroke gold medal.
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