LAS VEGAS — Flyweight Marlen Esparza, who claimed a bronze medal for the United States at the 2012 London Olympics but remained an amateur for the next four years, cruised to a unanimous decision win against Samantha Salazar on Saturday night on the Canelo Alvarez-Julio Cesar Chavez Jr. undercard at T-Mobile Arena.

Esparza, who turned pro on March 23, won 40-36 on all three scorecards in a four-round fight that was not at all competitive but did offer a major change in women’s boxing in Nevada.

For the first time in Nevada in many years, a women’s fight had rounds scheduled for three minutes rather than the two minutes usually used in women’s bouts. There was a women’s fight in at least 2007 that had three-minute rounds.

“I know it’s been done elsewhere, but tonight it feels really special doing it in this fight,” Esparza said. “I plan on staying at three minutes and not going back to two minutes, so I know we will need to be strategic about how I train and fight.”

Esparza (2-0, 0 KOs), 27, of Houston, dominated the fight, keeping the slower Salazar off balance with side-to-side movement and a snappy jab. Later in the fight, Esparza began to connect more regularly with her right hand against Salazar (2-4-1, 0 KOs), 31, of Dallas, who did not appear to land any telling punches in the fight.

“I loved having the extra minute. When I only had two minutes, I felt like my punches were reactive rather than being proactive,” Esparza said. “The extra minute gave me time to think and be more thoughtful and strategic in my punches. It felt like a board game, where I could be able to plan and be able to go four steps ahead.

“Once I have another fight that I am happy with, I want to start calling out other fighters so I can start to make it in the rankings. I want to stay at three-minute rounds and increase my next fight to six rounds and stay there for a bit.”

Esparza, who was the 2016 U.S. Nationals flyweight silver medalist, won her pro debut against Rachel Sazoff via shutout, also winning 40-36 on all three scorecards.