Why UFC Upsets Captivate Fans
Few things electrify MMA fans like a true upset — the moment when the entire world predicts one outcome and reality delivers the opposite. Upsets shake rankings, rewrite narratives, humble legends, and inspire new generations of fighters.
But more importantly, they reveal the heart of MMA: unpredictability. In a sport with four-ounce gloves, elite athletes, and endless stylistic clashes, anything is possible.
Here are the most shocking UFC upsets in history — the ones that shook arenas, silenced crowds, and instantly became part of MMA lore.
Matt Serra vs Georges St-Pierre (UFC 69)
This is the gold standard of UFC upsets.
Georges St-Pierre was the future of MMA: disciplined, powerful, fast, technical, and in his athletic prime. Serra was considered a journeyman who had earned a title shot by winning The Ultimate Fighter, not by climbing the rankings.
No one expected what happened.
- Serra clipped GSP early with hard overhands
- He swarmed with relentless pressure
- GSP couldn’t recover
- A TKO that stunned the world
It wasn’t just an upset — it was a complete shock to the system. It forced GSP to reevaluate everything and eventually helped him become even greater.
Why it stands out: The biggest skill gap upset in UFC title fight history.
Holly Holm vs Ronda Rousey (UFC 193)
Ronda Rousey was unstoppable. At least, that’s what everyone believed.
She had demolished opponents in seconds, she was a cultural icon, and the UFC promoted her as invincible. Holly Holm, a quiet former boxing champion, entered as a massive underdog.
But Holm saw opportunities no one else did.
- Perfect footwork
- Precise angles
- Zero panic under pressure
- Surgical striking at range
Her head-kick knockout became one of the most replayed moments in UFC history. Melbourne Arena went silent, then exploded.
Why it stands out: The moment the aura of invincibility around Rousey disappeared forever.
Michael Bisping vs Luke Rockhold (UFC 199)
This upset is iconic because of the circumstances.
Bisping took the fight on 17 days’ notice against a champion who had already beaten him decisively. Rockhold was confident — maybe overly confident — and most analysts predicted an easy defense.
But Bisping’s resilience shined.
- He pressured early
- Capitalized on Rockhold’s dropped lead hand
- Landed a left hook from hell
- Finished him against the cage
After a decade in the UFC and countless setbacks, Bisping completed one of MMA’s greatest story arcs.
Why it stands out: A short-notice title shot turned into a Hollywood-level redemption story.
Julianna Peña vs Amanda Nunes (UFC 269)
Arguably the biggest women’s MMA upset ever.
Amanda Nunes was the greatest female fighter alive, riding a 12-fight win streak and dominating every champion before her. Peña, however, was relentless in her belief that she could win.
What followed shocked everyone.
- Peña refused to back up
- She pressured with straight punches
- Nunes tired quickly under unexpected resistance
- Peña took the back and submitted her
Fans couldn’t believe what they were watching — the GOAT looked human.
Why it stands out: The most unexpected title fight win in modern women’s MMA.
Chris Weidman vs Anderson Silva (UFC 162)
Anderson Silva’s dominance felt untouchable. He was the most creative, deadly, and unpredictable striker the UFC had ever seen.
Yet his biggest strength — confidence bordering on playfulness — became his downfall.
During the fight:
- Silva dropped his hands
- Played mind games
- Leaned away from strikes
- Misjudged Weidman’s distance
Weidman’s left hook connected perfectly, ending Silva’s legendary streak.
Why it stands out: The fall of the greatest middleweight of all time.
TJ Dillashaw vs Renan Barão (UFC 173)
Renan Barão entered the cage with 32 fights unbeaten — one of the longest streaks in MMA history. Dillashaw, meanwhile, wasn’t even supposed to be in the title picture.
This was expected to be a tune-up fight for Barão… but Dillashaw had other plans.
- He used footwork far ahead of its time
- Mixed angles and combinations brilliantly
- Landed a clean head kick that changed everything
- Dominated for five rounds before finishing Barão
This was an upset in skill, dominance, and expectation all at once.
Why it stands out: Not just an upset — a complete dismantling of a dominant champion.
Nate Diaz vs Conor McGregor (UFC 196)
This wasn’t a title fight, but the moment was massive.
Conor McGregor was the sport’s biggest star, full of mystique and momentum. Diaz took the fight on short notice, looked unbothered, and delivered the famous line: “I’m not surprised, motherf**er.”*
During the fight:
- Diaz survived McGregor’s early power
- Turned the pressure up
- Hurt McGregor with boxing volume
- Took him down
- Choked him out
The upset shocked the world and produced one of the UFC’s most iconic soundbites.
Why it stands out: A short-notice, narrative-crushing moment that shifted the sport’s direction.
Frankie Edgar vs BJ Penn (UFC 112)
BJ Penn, at that time, was viewed as an unbeatable lightweight. He was the king of the division, technically flawless, physically dominant, and mentally unshakeable.
Frankie Edgar was supposed to be too small, too light, too inexperienced.
Instead:
- Edgar outworked him
- Used footwork and movement to stay elusive
- Mixed striking and grappling beautifully
- Won a close but legitimate decision
This upset marked the beginning of the end for Penn’s lightweight reign.
Why it stands out: A new era was born the moment the decision was read.
What Makes an Upset Truly Shocking?
Upsets aren’t just about odds. They happen when:
- A champion appears unbeatable
- Media narratives heavily favor one fighter
- Style matchups are misjudged
- A challenger brings something unexpected
- The crowd, commentary, and even coaches are stunned
In MMA, the beauty lies in the unknown — one punch, kick, knee, or decision can rewrite history.
Why Fans Never Forget These Moments
These upsets stuck because they didn’t just change fighters — they changed divisions, careers, and the sport itself.
- The Serra upset made GSP evolve into the greatest welterweight ever
- Holm derailed an entire era of promotion built on Rousey
- Bisping became a legend overnight
- Peña reminded everyone that belief is a weapon
- Weidman ended an era of Silva’s showmanship
- Dillashaw ushered in a new level of striking footwork in MMA
- Diaz vs McGregor became cultural, not just competitive
- Edgar reshaped the lightweight division
These moments remind fans why we watch: because anything can happen.
Final Thoughts
MMA is unpredictable by nature—but upsets are the heartbeat of the sport. They inspire, shock, divide fans, and spark debates that never end.
The next historic upset could happen in the very next event. That’s the magic of the UFC.