It's hard to imagine, but this time a year ago, Amanda Nunes was entering a bantamweight title fight as a challenger.
She was down on the card beneath names like Brock Lesnar and Jon Jones at UFC 200, ready to do battle with Miesha Tate at a time when it looked like Tate was just rounding into her own as a championship-level fighter.
Rousey was to return from a sabbatical imposed by the left shin of Holly Holm at UFC 193, ready to emerge from the shadows after a year in exile to reclaim her place atop the women's 135-pound mountain.
December 30 was the date. UFC 207 was the event.
And that's about all that went right for Rousey.
After some promotion that was so bizarre and stagnant as to almost border on anti-promotion, Rousey stepped into the cage with Nunes with her trademark scowl and snorting intact. She passed the eye test, but once the bout started, it was clear that was the only test she would pass.
Nunes stalked Rousey from the opening bell, totally disrespecting the hands she'd tirelessly worked with coach Edmond Tarverdyan and disrupting the clinch work and bullying tactics she'd tirelessly worked since her years as an Olympic judoka.
At every turn, Nunes flustered Rousey, finally landing one big shot that changed the complexion of the fight. She then landed many more, sending Rousey flailing across the cage and chasing her down to deliver more punishment.
Though she never put her opponent on her behind, referee Herb Dean called a stop to the bout after only 48 seconds, with Rousey limply standing wasted against the cage.
UFC 213 on Saturday marks Nunes' first defense since that dominant, star-making showcase. She'll fight Valentina Shevchenko, over whom she already holds a win, in the main event.
Win or lose, though, everyone will always remember that time she did a number on the most famous player in the game and sent her reeling into retirement.
Check out the fight below.