Oddsmakers don’t appear to have much faith in Amanda Nunes’ ability to snap Cris Cyborg’s 13-year unbeaten run.

Cyborg (-300) opened as a massive 3-to-1 betting favorite over Nunes (+230) on Friday morning ahead of a potential superfight between the UFC’s current female featherweight and bantamweight champions, according to odds released by online bookmaker Bovada. The news comes as Cyborg and Nunes continue to rage against one another on social media in debate over the date of their proposed meeting, with Cyborg calling for a Sept. 8 date at UFC 228 and Nunes requesting a Dec. 29 meeting at UFC 232.

Cyborg (20-1, 1 NC), the UFC women’s featherweight champion, is undefeated since stumbling in her professional MMA debut in 2005. Over that time, she has captured a litany of major titles — from UFC to Strikeforce to Invicta FC — while establishing herself as one of the greatest female fighters to ever compete. Her résumé includes victories over Holly Holm, Gina Carano, Tonya Evinger, Marloes Coenen (x2), and Shayna Baszler, among others.

Nunes (16-4), meanwhile, rides a career-best seven-fight win streak into the potential superfight against her Brazilian countrywoman. The reigning UFC women’s bantamweight champion, Nunes has defeated a slew of notable names over the course of her title run, including Ronda Rousey, Miesha Tate, Valentina Shevchenko (x2), Raquel Pennington, and Sara McMann.

If Cyborg vs. Nunes does take place, Nunes will vie for the chance to become only the third champion — and first woman — in UFC history to hold two titles simultaneously, joining the ranks of Conor McGregor and Daniel Cormier.