If you ever want to humble a room full of experts, just ask them to predict MMA fights. The sport has a singular talent for making fools of certainty. No matter how dominant a champion appears, no matter how lopsided the betting odds look, the cage has a way of rewriting every script.
We have been around this sport long enough — training in gyms, working corners, building fighters' careers — to know one thing above all else: never count anyone out until the referee waves it off. The upsets that land hardest are never random. They tell a story about preparation, game plans, and what happens when the favourite stops respecting the danger in front of them.
Here is a look at the most shocking upsets of recent MMA history, starting with some modern classics and arriving at 2026's seismic main event.
Holly Holm ends Ronda Rousey's era (UFC 193, 2015)
Every conversation about MMA upsets begins here. Ronda Rousey had become bigger than the sport itself: a crossover celebrity, an untouchable champion, the face of women's combat sports globally. Holly Holm, a former boxing world champion, was a 12-to-1 underdog walking into UFC 193 in Melbourne.
What followed was a masterclass in game-planning. Holm controlled the distance with her footwork, negated Rousey's signature grappling, and finished the fight with a brutal head-kick knockout in round two. The upset ended Rousey's undefeated streak and fundamentally changed how the sport viewed women's MMA — proving the division had genuine depth and that elite boxing defence could neutralise world-class judo.
The lesson? Dominance built on one set of skills becomes a vulnerability the moment an opponent holds the perfect counter-skill set.
Matt Serra over GSP: the blueprint of chaos (UFC 69, 2007)
No all-time upsets list exists without this one. Georges St-Pierre entered UFC 69 as arguably the finest pound-for-pound fighter on the planet. Matt Serra, who had earned his title shot through a reality show, was priced as a +850 underdog. Nobody outside Serra's own corner believed he had a realistic path to victory.
Serra found it in 3 minutes and 25 seconds of the first round, overwhelming St-Pierre with a flurry of punches that forced the stoppage. It remains one of the biggest upsets in the history of the sport, and it serves as the ultimate reminder: in MMA, one clean shot can collapse even the most carefully constructed mountain of favouritism.
Julianna Peña submits the "unbeatable" Amanda Nunes (UFC 269, 2021)
By December 2021, Amanda Nunes had spent years cementing her legacy as the most dominant fighter in women's MMA history. She entered UFC 269 on a twelve-fight winning streak, holding titles in two divisions simultaneously. Julianna Peña was a 6.5-to-1 underdog.
Peña submitted Nunes with a rear-naked choke in round two. The MMA world went quiet for a moment, then erupted. Few upsets in the sport's recent history carry the same weight, because few opponents carried Nunes' level of verified, cross-divisional dominance going in. Peña's win forced a re-evaluation of what it means to be "untouchable" in this sport.
Sean Strickland shocks Israel Adesanya (UFC 293, 2023)
Heading into UFC 293, Israel Adesanya was a technical striker of the highest order, one of the most decorated champions in middleweight history. Sean Strickland was seen as a durable gatekeeper who talked more than he delivered. Adesanya was the clear favourite.
Strickland won a decisive unanimous decision, controlling Adesanya with relentless forward pressure and sharp boxing over five rounds. The result was a genuine shock to the system, not because Strickland was an unknown quantity, but because his style was considered the wrong kind of pressure to trouble a counter-striker of Adesanya's calibre. The cage, once again, disagreed with the consensus.
Strickland, to his credit, has continued to defy odds. By mid-2026, Tapology's community had logged him among the top all-time upsets twice in a relatively short span.
Reinier de Ridder stops Bo Nickal (UFC on ESPN, 2025)
Bo Nickal arrived in the UFC with enormous expectations. A decorated NCAA Division I wrestling champion, he had dispatched his early opponents with surgical efficiency and was quickly positioned as a future middleweight contender. Reinier de Ridder, despite an impressive body of work in other promotions, was the underdog when the two met.
De Ridder needed just two rounds to finish Nickal with a knee strike, earning a knockout win that stopped the hype train in its tracks. It was a timely reminder that wrestling pedigree, however impressive on paper, must be paired with the full mixed martial arts toolkit to survive at the elite level.
Gaethje defeats Topuria at UFC Freedom 250 (June 2026)
This is the upset that will define 2026. On 14 June, at the South Lawn of the White House in Washington D.C., Justin Gaethje entered the cage to face Ilia Topuria as a more than 6-to-1 underdog. Topuria was the undefeated lightweight champion, a two-division titleholder who had steamrolled Alexander Volkanovski, Max Holloway, and Charles Oliveira on his way to the top.
Gaethje, at 37 years of age and widely believed to be past his peak, had other ideas. After surviving a punishing second round that included brutal body shots from the champion, Gaethje turned the fight in round three with a right hand that appeared to damage Topuria's orbital bones. Topuria's corner made the call to stop the contest at the end of round four, handing Gaethje the lightweight title by TKO.
The moment — Gaethje performing a backflip on the South Lawn under the lights of the White House — was immediately iconic. The MMA media ranked it among the most significant upsets in UFC history, and the betting odds made it one of the biggest shocks on record for a title fight.
What every upset has in common
Looking across these moments, patterns emerge that go beyond luck or chance.
- A counter-style advantage: Holm had the boxing to neutralise Rousey's grappling. Strickland had the pressure to disrupt Adesanya's counter-timing. The underdog almost always brings a specific tool the favourite has not been forced to solve.
- Mental resilience over the favourite: Upsets rarely happen to champions who are fully locked in. Belief in one's own invincibility is itself a vulnerability. A fighter who does not respect the danger in front of them becomes predictable.
- Conditioning as a weapon: Gaethje survived a round that might have finished others, then imposed his own pace. Peña wore Nunes down before seizing the submission. Conditioning, built round by round in the gym, is often the invisible factor in an upset.
- A fearless game plan executed with precision: Nobody walks into these fights and improvises their way to a title. The corner work, the preparation, the technical planning — all of it matters.
Why upsets keep the sport alive
MMA's unpredictability is its greatest commercial asset. The moment a champion is perceived as unbeatable, the gate and the attention grow — because somewhere, a challenger and their team are quietly building the argument to the contrary. Upsets do not undermine the sport's credibility. They validate its fundamental promise: any given night, in any given cage, the result is genuinely unknown until the final bell or the stoppage.
That uncertainty is what fills arenas, drives streaming numbers, and keeps fans arguing for weeks. It is also what makes the management of a fighter's trajectory so critical. Choosing the right moment, the right opponent, and the right stage to make a statement — these decisions shape careers.
The underdog mentality in European MMA
European fighters understand the underdog position better than most. Building a career on this continent means fighting with fewer resources, less media coverage, and less promotional machinery than the established names in the United States or the major Asian markets. And yet, European fighters continue to punch above their weight on the global stage.
That is not an accident. It is the product of hunger, technical quality, and the kind of resilience that cannot be manufactured — only lived. Every fighter in our BDZ Management roster carries exactly that mentality: the knowledge that the path is longer, and the commitment to walk it anyway.
Lessons for fighters and their teams
The great upsets of recent MMA history are not just entertaining television. They are a curriculum. They teach coaches, managers, and fighters the following:
- Respect every opponent, regardless of what the odds board says
- Trust the process during the difficult rounds
- Build your strengths around the opponent's specific weaknesses
- Believe in the game plan when the pressure is at its highest
In combat sports, that is the only preparation that matters.