Ronda Rousey challenges current UFC bantamweight champ Amanda Nunes on Dec 30 in Las Vegas at UFC 207

Former UFC female bantamweight champion Ronda Rousey is returning to the octagon ring to challenge current champion Amanda Nunes. However, Julianna Pena, winner of the first women’s “Ultimate Fighter” season in 2013 is not happy with the Dec 30 comeback of Rousey.

It took Rousey, who used to be undefeatable in her weight division until a head kick by former boxer Holly Holm in November 2015 caused a lot of changes in UFC. The title since then changed hands twice with the champion losing the belt on their next fight to the challenger.

After Holm’s unexpected victory, her reign was short-lived because she could not wait more than six months for Rousey to recover from injuries she gave the ex-champ for a rematch. Holm accepted the challenge from Miesha Tate at UFC 196, and lost the title on the fifth round.

But the belt did not stay long with Tate who lost it to Amanda Nunes at UFC 200. Among the MMA fighters who itched to grab the crown from Nunes were Pena and Cris “Cyborg” Justino. But with UFC’s announcement on Sunday that Rousey’s much-anticipated comeback would be held at the Las Vegas T-Mobile arena, as Fortune reported, Julianna Pena threatened to quit UFC over allegations of special treatment given to Rousey.

“Never in the history have I ever heard of somebody have a no-controversy brutal knockout, then quit the sport, and then comeback and get a title shot right away. The girl is mentally weak and Amanda Nunes is going to [expletive] knock her out and expose her ass. She’s literally the worst fighter on the roster, and I can’t stomach the fact that I’m not getting the title shot,” Yahoo quotes Pena who calls Rousey’s return “BS.”

And if Rousey gets back the title, UFC President Dana White just hinted she would defend the crown from challenger Justino, further causing Pena to fume.