Amanda Serrano’s badassery knows no bounds.

Ten days after defending her featherweight crown, Serrano on Wednesday offered to step in to face former two-division UFC champion Amanda Nunes next week once it was revealed that Nunes’ original opponent, UFC 135-pound champion Kayla Harrison, was forced to pull out of the fight after undergoing neck surgery.

“If UFC and Amanda Nunes are thinking of a replacement, I would love the challenge as I’m still in fight shape,” Serrano said on social media. “Hope the champ (Harrison) recovers well.”

Usually, it's MMA fighters who are the ones looking to crossover into boxing, but “The Real Deal” Serrano has a history of competing in mixed martial arts.

Serrano is 2-0-1 in MMA, with both wins coming by way of submission; she fought twice in MMA in 2018 and once in 2021. Serrano, a surefire future Hall of Fame boxer, sports a 48-4-1 record in the ring with 31 knockouts and titles across seven divisions.

“This isn’t to disrespect Amanda Nunes,” said Serrano. “I think she’s the greatest of all time in MMA. I also know she has incredible hands and loves to use them. I’ve competed in both MMA and jiu-jitsu. Anyone that has ever done MMA and BJJ has always dreamt of competing in the biggest stages and UFC.

“My nephew Jovan is the captain of his varsity wrestling team, and I train with him a few times a week just to give him extra work. I love kicking, so I never stopped training that either. Much respect to and for ‘The Lioness’ Nunes.”

Most Valuable Promotions CEO Nakisa Bidarian, who promotes Serrano and is also a former UFC executive, said: “Amanda Serrano is one-of-one. She has confirmed with me she would 100 percent step in.”

Harrison vs. Nunes was supposed to take place on January 24 at T-Mobile Arena in Las Vegas as the co-main event of UFC’s debut show on Paramount+.

A replacement opponent hasn’t been announced yet, but if Serrano gets the call, she’d be the most significant boxer to crossover into the UFC since James Toney fought Randy Couture in 2010 and lost in the first round by an arm triangle choke.

The knockout artist Nunes (23-5, 13 KOs, 4 submissions MMA) holds wins against the likes of Ronda Rousey, Cris Cyborg, Miesha Tate, Holly Holm, and Valentina Shevchenko (twice). Nunes retired in 2023 following a decorated career, but is ready to give it another go at 37.

Serrano is The Ring’s No. 5-rated pound-for-pound fighter and is coming off a unanimous decision win and defense of her featherweight title against Reina Tellez on January 3 in Puerto Rico.

The 37-year-old Serrano’s profile has skyrocketed in recent years due to her scintillating rivalry and trilogy with Katie Taylor, and by partnering with Jake Paul and fighting on Netflix events that have generated massive viewership numbers.