Disgraced South Korean swimmer Park Tae-hwan concedes it has been "hell" since he failed a drug test that has landed him with an 18-month ban.
The former Olympic champion has been suspended until next March, putting his participation at the 2016 Rio Games in doubt.
Park will be free to compete in Brazil next year, but is well aware he has made a costly career mistake.
"The last few months since the doping results came out have been hell," said the 25-year-old.
"I want to say sorry to the people for not apologising, not explaining the situation and not opening my mind sooner."
On his chances of representing South Korea in South America next year, he said: "The International Swimming Federation has left the door open for the Olympics, but nothing has been decided yet."