U.S. swimmer Ryan Murphy raised questions about the presence of doping in swimming following a second-place finish in the men's 200-meter backstroke on Thursday.

Driving the news: Murphy, who won gold in the 200-meter backstroke race in Rio, said following his race: "At the end of the day, I do believe there’s doping in swimming. That is what it is."

• Murphy, who sat near Evgeny Rylov, the Russian who beat him in the 200m backstroke, was asked if he thought the race was clean during a post-race interview.
• "What’s frustrating is that you can’t answer that question with 100% certainty," Murphy said. "Over the years that has kind of come out. I can’t answer that question."
• After the post-race interview that created a stir, Murphy sought to reframe his original answer. "I'm not accusing anyone of anything," he said outside the venue, according to Yahoo! Sports. "Congratulations, Evgeny,” he said. “I want Evgeny to get his due.”
• Rylov for his part, said he did not think Murphy was accusing him of cheating. “Ryan has all the right to think what he does and say what he says. The time will tell. He didn’t accuse me of anything, so that’s why I don’t have anything against him," he said.
• “I have always been for clean conditions (in the sport)," he said when asked if he races clean. "I always do my tests and I’m devoting my whole life to this. I don’t even know how to react to that.”

The big picture: Murphy did not accuse Rylov of cheating, nor did he object to Russian athletes competing in the Games. Russia has been accused by anti-doping regulators of running one of the most sophisticated doping schemes in the history of international sports.

• "I don’t have time to get involved in this situation. But there’s a situation, and that’s a problem. I’m sorry that there’s a situation, but I don’t know enough about it to give a 100% certain answer," Murphy said.