Russia's Yulia Efimova claimed Tuesday that fierce rival Lilly King probably regretted her behaviour at the Rio Olympics when the American refused to shake hands with the former doping offender.
King, then just 19, snubbed Efimova at the 2016 Games after winning gold in the 100m breastroke and slammed the decision to let drug-tainted swimmers compete.
But Efimova, beaten by King over the same distance at the world championships in Gwangju on Tuesday, said she believed King might think differently about her actions three years on.
"If you take Lilly King and ask her if she'd do the same as she did (then), I think she would never say I did it right," she said.
"Probably she'd think she did it wrong."
The pair's feud subsequently morphed into one of the most bitter rivalries in women's swimming, but both athletes have called a fragile truce.
"We are still fighting in the pool but not in life," said Efimova. "She's not a friend... but it's just a good relationship between people who swim."
Efimova was suspended for 16 months after testing positive for a banned steroid.
But the 27-year-old was cleared to compete in Rio after the Court of Arbitration for Sport (CAS) ruled athletes cannot be banned on the basis that they have been previously sanctioned.
After taking silver behind King again, Efimova spoke of her frustration that their contests were hyped in the sort of way boxing matches are promoted.
"It's like a fight, (where) they make big commercials," she said. "I feel like we have the same kind of thing."
Her comments came after Briton Duncan Scott, who tied for bronze in the 200m freestyle, refused to shake winner Sun Yang's hand on the podium -- as Australian Mack Horton had after losing to the Chinese giant in an earlier final.
Sun is competing under a doping cloud after a leaked FINA report alleged he destroyed blood samples after being visited by testers last year.
"The athletes are showing that they're standing up for themselves and they're standing up for what they believe in so I commend them," said King.
"That's incredibly brave to do something like that and I'm glad they're making a change in the sport."
Asked about Efimova, she said: "I wouldn't say we have completely moved on but we are definitely more cordial than we have been.
"I know she's going to come for me in races," she added.
"She always keeps me on my toes."