Many feel that top title contender Valentina Shevchenko (14-2) would have beaten women's bantamweight champion Amanda Nunes (14-4) had their first fight gone five rounds.
Shevchenko will get the chance to prove them correct Saturday, when she faces Nunes for the title as a minus-125 betting favorite (wager $125 to win $100) at sportsbooks monitored by OddsShark in the main event of UFC 213.
Shevchenko opened as a slight underdog but has since flipped to chalk status, while some books have this championship bout listed as a pick 'em.
Regardless, it is an intriguing matchup between arguably the best striker in the UFC (Nunes) and the top tactician in the division (Shevchenko). In their first meeting, at UFC 196 in March 2016, Nunes won a unanimous decision by scores of 29-28, 29-27 and 29-27. She started fast but faded in the third round, holding on to win on the judges' scorecards.
This time around, the 29-year-old Nunes is a minus-105 underdog, and she remains the lone Brazilian champ in the UFC after Jose Aldo lost the featherweight title to Max Holloway at UFC 212 in Rio de Janeiro.
Nunes upset former champ Ronda Rousey as an underdog at UFC 207 on December 30 with a first-round TKO. She took the title away from Miesha Tate with a first-round rear-naked choke submission at UFC 200.
Meanwhile, Valentina has a strong kickboxing background, losing just twice in 60 fights. She is 3-1 in the UFC, with back-to-back wins over Holly Holm and Julianna Pena since falling to Nunes. Her only other MMA loss came against UFC vet Liz Carmouche via second-round TKO (doctor stoppage) in C3 Fights back in 2010.
The co-main event will also see a championship belt on the line, when Australian Robert Whittaker (18-4) meets Cuban Yoel Romero (13-1) for the interim middleweight title. Whittaker is the minus-135 favorite and has gone 6-0 since moving up to 185 pounds from 170, earning four performance bonuses along the way.
Whittaker's last loss came as a welterweight against Stephen Thompson by first-round TKO at UFC 170 in February 2014.
The 40-year-old Romero is listed as a plus-105 underdog despite going unbeaten in the UFC, at 8-0. He has picked up five performance bonuses in his eight bouts with the promotion, knocking out six opponents, with five of those KOs coming in the third round.
The interim belt is up for grabs because middleweight champ Michael Bisping has not fought since October 2016 and seemingly wants to fight Georges St-Pierre rather than Romero.