Jessica McCaskill insists Katie Taylor "hasn't changed very much at all" in the three years since their fight, in an ominous warning ahead of a potential rematch.
Taylor won their meeting via unanimous decision in December 2017 but McCaskill has since become the undisputed welterweight champion and a second fight was mentioned by promoter Eddie Hearn as a possibility.
"We gave Katie a great fight and almost knocked her out with a left hook," McCaskill told Sky Sports.
"It wasn't that we weren't prepared. We did everything that we were supposed to do. I wouldn't go back and change anything - if I was on the wrong path, I wouldn't be where I am today.
"I exposed a lot of her downfalls as a boxer. Then, everybody wanted to fight her."
Chicago's McCaskill was fighting just her seventh pro bout after a brief amateur career, and was in her first world title fight and her first venture overseas, when she fell short against Taylor.
But she became a world super-lightweight champion in her next fight and, last summer, completed a huge upset against Cecilia Braekhus to win every major welterweight title.
That shock result ended the 36-fight undefeated record of Braekhus and has shot McCaskill back into the conversation to oppose Taylor again.
"We are doing the Jessica McCaskill vs Cecilia Braekhus rematch in early March and I think you will see Katie fight the winner in the summer," promoter Hearn told Sky Sports.
McCaskill's career has skyrocketed to new heights since she first exchanged punches with Taylor but she believes her rival has not evolved.
"She hasn't changed very much at all," McCaskill said.
"Three years ago I was very green, after coming into the sport with only 25 amateur fights. In Chicago I was fast-tracked.
"I have incorporated a nutritionist, a strength and conditioning coach and different sparring over the years. We are more experienced.
"I wouldn't say it didn't go right for me. People ask what I would do differently? What did I learn?
"I learned that my team is prepared for the big stage. That was my biggest fight at the time.
"I had headlined locally in Chicago but fighting in a different country was an experience that I took a lot from.
"We were collectively prepared as a team.
"It made a big opening for female boxing. It kept the female boxing train going.
"Since then, I have only fought world champions. Before, it was only smaller fighters. Now I fight completely at the top level."
Taylor's next fight is pencilled in for April and she is also considering facing Natasha Jonas in 2021.