British discus thrower Brett Morse has removed Twitter comments accusing Belarusian women's shot put gold medallist Nadzeya Ostapchuk of doping.
On Monday, Welshman Morse failed to qualify for the Olympics discus final and later tweeted: "I've had a bad day but it could be worse, I could look like Ostaptchuk [sic]."
He then made the doping accusation.
Morse's agent, Jamie Baulch told the BBC: "I'm going to tell him to remove it".
On hearing of Morse's comments, retired athlete Baulch added: "I think people say things on Twitter and they don't realise who's listening".
And a spokesman for Sport Wales, which is responsible for improving sport performance in Wales said: "Twitter and other forms of social media have proven a great way for Welsh sport to promote itself.
"However, they are very public forums and individuals have a personal responsibility for how they use them."
On Monday, Morse, 23, from Penarth, had failed in his first attempt to meet the designated qualifying distance to progress to the final, or be among the top 12 throwers, earning a red flag as his toes strayed over the edge of the circle.
His only successful throw came at the second attempt, but he overstepped the circle again on his third and final effort and he departed the Olympic Stadium having failed to reach anywhere near his personal best of 66.06 metres.
Morse said after going out of the competition: "I'm actually in my best shape and my technique's a lot better... but for some reason in competition it just goes to pieces. It's frustrating."