The race "probably wasn't clean," Murphy, 26, told a reporter.
It was an apparent reference to Russia's history of state-sponsored doping, which has been extensively documented even as the Kremlin rejects such stories.
Murphy's comment was not the first time an American Olympian used the international stage to talk about doping problems in their sport. But, in this case, Murphy took pains to insist he was not calling out any specific competitors as one of them sat right next to him in front of the cameras.
The unusual back-and-forth began after Murphy competed in the men's 200m breaststroke. He won silver behind Evgeny Rylov, from Russia. (In Tokyo, Russian athletes are technically competing for the Russian Olympic Committee as part of an anti-doping penalty.)
After exiting the pool, Murphy — who also placed third in a race in Tokyo behind Rylov and Kliment Kolesnikov, both of the ROC — told the reporter that he believed the race involved illicit substance use and indicated that officials had not done enough to weed out wrongdoing.
Murphy did not specifically name the ROC or the country's doping scandal, which led Russia to be formally booted from the 2018, 2020 and 2022 Olympics.
But the topics of Russia and doping are closely intertwined and Olympians have discussed it before.
"I've got about 15 thoughts. Thirteen of them would get me into a lot of trouble," Murphy said immediately after his race after the reporter asked him about fairness.
Photo by Stanislav KrasilnikovTASS via Getty Images
"It is what it is. I try not to get caught up in that," Murphy said.
"It is a huge mental drain on me to go throughout the year that I'm swimming in a race that's probably not clean, and that is what it is," he said. "The people that know a lot more about the situation made the decision they did. It frustrates me, but I have to swim the field that's next to me. I don't have the bandwidth to train for the Olympics at a very high level and try to lobby the people who are making the decisions that they're making the wrong decisions."
The suggestion — which Murphy said was not an allegation, but an honest reflection of doping problems in swimming — dominated the questions at a post-race press conference with him, Rylov and Great Britain's Luke Greenbank, who won bronze.
Olympic athletes are routinely drug tested, often immediately after the competition.
There is no evidence any of the swimmers in Friday's race with Murphy were using banned substances.
At the press conference, Rylov, 24, was asked to respond to Murphy. "Honestly, I'm not aware of this comment so I cannot react to something that I haven't heard," he said, according to a translation.
At the same time, Murphy joined Rylov and Greenbank at the press conference and was asked if he believed their race was clean.
He repeated his earlier stance, referencing the history of doping problems but declining to be more specific. He said it was because of these problems that he could not know for sure.
"I think the thing that's frustrating is that you can't answer that question with 100 percent certainty, and I think that over the years that's kind of come out," Murphy said. "And so I can't answer that question. I don't know if it was 100 percent clean and that's because of things that have happened over the past."
A reporter then asked Rylov directly: Was Murphy referring to him? Does he dope?
Photo by FRANCOIS-XAVIER MARIT/AFP via Getty Images
"I have always been for clean competition, I'm always tested, I will fill out all the forms and so from the bottom of my heart I am for a clean sport," Rylov said. "I am devoting my whole life to this sport, right? So I don't know even how to react to that. Ryan — well he didn't accuse me of anything, therefore I'd rather not react to what he said."
Another reporter asked about the importance of his gold medal win.
"I learned my lessons and did my homework, right, and now I'm where I am now," Rylov said about his 2016 Olympic showing, in which he won a bronze.
Murphy, too, praised Rylov. "I think to be clear I've never made— my intention is not to make any allegations here," Murphy said. "Congratulations to Evgeny, congrats to Luke. I think they did an incredible job. They're both very talented swimmers. I think they both work really hard. They've got great technique."
But, he went on: "At the end of the day, I do believe there's doping in swimming and that is what it is."
Echoing the comment he'd made near the pool after the race, Murphy said it wasn't his place to solve the broader issues. But he repeated that he took issue with them nonetheless.
"There's people that know a lot more about this situation than I do," he said. "I am training to be the absolute best athlete I can be, and so I don't have time to get involved in this situation. But there is a situation."
After leaving the press conference, Murphy briefly expanded on his thoughts as a small group of press trailed him. He said the original reporter had asked him if he thought there was doping in swimming "and that's a really hard question to be asked."
"It's like, yeah, a bunch of emotions, a bunch of thoughts run through your head when you are asked a question like that," he said. "And are they all positive thoughts? No, of course not. … And that's essentially what I was [meaning]."
One reporter suggested Murphy had "completely ruined" Rylov's victory.
No, no, no, Murphy said.
"Congratulations to Evgeny. I want Evgeny to get his due. He did an incredible job."
Later, Rylov posted a statement on Instagram in both Russian and English, writing in the latter, "We talked with Ryan and once again made sure that it was a misunderstanding. We have never had any complaints against each other and remain good rivals. We both advocate that the sport should be clean."
Murphy posted the Instagram on his personal Story and added, "Enjoy competing against you. Looking forward to many more great races in the future. Congrats on the win."
Murphy is not the first American swimmer to reference doping scandals during the Games or suggest some of the athletes have done something wrong.
Fellow American medalist Lilly King famously criticized Russian swimmer Yulia Efimova and accused her of "drug cheating" in 2016. Efimova, who has been suspended for doping in the past, said King was "immature."
Photo by Maddie Meyer/Getty Images
"I think if I feel the need to have the final word on something that's doping-related, then I guess I'm fine with speaking out about that," King said later.
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