Lilly King and Yulia Efimova's Olympic rivalry was never destined to stay confined to the pool at the Olympic Aquatics Stadium, not with King's sudden prominence as a doping vigilante.
Now, with the swimming events in Rio all finished, Efimova is opening up about the emotional toll of King's outspokenness.
"It was war, Efimova told USA Today on Saturday (US time). "It was like a nightmare. This completion is a relief because I love racing, but this was more like a war."
The inciting moment happening during last Sunday's 100m breaststroke semifinals, when Efimova won her heat and held up an index finger signaling "No 1."
The only problem, at least for King, was that Efimova was originally among the seven swimmers banned from the Rio Games for testing positive for a banned substance, a sentence that was overturned shortly before the breaststroke event. Efimova had previously been given a 16-month suspension for performance-enhancing drug use in 2014 and had a suspension for using meldonium overturned earlier this year. Suffice to say, King didn't like Efimova's "No 1″ sign.
She responded with a wag of a finger that blossomed into a full-fledged campaign for clean swimming that has earned the 19-year-old adoration among fans. King also said Efimova should not be allowed to compete.
"You wave your finger No 1, and you've been caught drug cheating?" King said on NBC after her semifinal. "I'm not a fan."
Efimova, on the other hand, earned the wrath of a fan base happy to get behind an outspoken, spunky teenager who, oh yeah, beat Efimova in the 100m breaststroke final for a gold medal. Efimova said King turned the Olympics into an intercontinental war in which she was the common enemy.
That meant boos almost every time Efimova walked out onto the pool deck. It meant tears in awkward press confidences in which she, the silver medalist, had to sit next to King, avoiding eye contact. It means the Russian 24-year-old is re-considering returning to Southern California, where she has trained since she was a teenager.
"(King) is young," Efimova told USA Today. "She doesn't know sometimes how life is going on. I hope that she changes, changes her mind and everything."
King narrowly edged out Efimova for gold in the women's 100 breaststroke final. Efimova settled for silver, a result she would duplicate Thursday in placing second in the 200 breaststroke. King failed to reach the final.