Rivera-Calanoc was slated to fight Cassie Rodish at the event, but England’s Simona Soukupova has stepped in on short notice to accept the bout.
The Rodish vs Soukupova bout takes place on Apr. 5 at Ameristar Casino Hotel in Kansas City, Missouri, and a top ten ranking in the women's atomweight division may be on the line.
MMARising.com ranks Rodish No. 6 in the 105-pound class, while Soukupova hasn't yet cracked the top ten. A victory by Rivera-Calanoc would have been a huge upset, and Soukupova will also be taking on the role of the underdog.
Rodish is riding a four-fight winning streak that includes two victories inside the Invicta FC cage, while Soukupova won three of her past six.
As for Rivera-Calanoc, no timetable has been set for her return. She's extremely disappointed that she will not be competing on the historic Invicta FC 5 card.
"@TimWMMAToday @cassierodish Thanks I except those wishes :) and me too. Just REALLY SUCKS I WANTED TO FIGHT BAD!!!!" she tweeted on March 11.
Invicta Fighting Championships 5 takes place on April 5 at the Ameristar Casino Hotel in Kansas City, Missouri, and the event will be headlined by a pair of championship fights.
Jessica Penne vs Michelle “The Karate Hottie” Waterson will serve at the event headliner, as the Invicta FC Atomweight Championship belt is on the line.
Vanessa Porto squares off against Barb Honchak for the Invicta FC flyweight belt. Rodish vs Soukepova is expected to cap off the Invicta FC 5 undercard.
With Rivera-Calanoc off the Invicta FC 5 bill, it's up in the air at this point if UFC star Miesha Tate will still be appearing at the event. Tate often shows up to Invicta FC events in support of Rivera-Calanoc, but she has a UFC fight coming up on Apr. 13 and "The Night Queen" falling off the Apr. 5 bill may be enough to keep her from attending.