The Biggest UFC Upsets Of All Time  

Ranker Sports
97 votes 13 voters 25 items

List Rules Vote up the most unexpected UFC results in history.

The biggest UFC upsets have proved that no result is certain in the octagon. A huge appeal for UFC events in 2019 is the fun of knowing anyone can pull off an upset on the right night. All the MMA fighters are quite skilled and spend their lives training for their upcoming fights. Even the biggest underdog has been preparing for months at a high level for that night to surprise everyone with a shocking KO. 

The UFC best upsets to take place in the company’s long history will be featured here. Fans were absolutely stunned at the results of these fights in real time. Many betters lost money thinking the favorite would be a safe play, only to see the underdog finish things off with a knockout.

The unpredictability of UFC is most highlighted by the knockouts in play here. Vote up for the results that surprised you the most when they happened, and help decide just which fight had the biggest upset in UFC history!

Matt Serra Vs. George St. Pierre
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Video: YouTube

Event: UFC 69
Date: April 7, 2007

Matt Serra pulled off the upset against the dominant George St. Pierre with some brutal punches for the knockout victory.

A shocking ending?
T.J. Dillashaw Vs. Renan Barao
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Video: YouTube

Event: UFC 173
Date: May 24, 2014

The headkick and punches earned T.J. Dillashaw a huge upset victory, stealing the night's best moment at UFC 173.

A shocking ending?
Holly Holm Vs. Ronda Rousey
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Video: YouTube

Event: UFC 193
Date: November 14, 2015

The unbeatable Ronda Rousey suffered her first defeat at the hands of Holly Holm. Fans were shocked at Rousey's streak ending with the Holm knockout victory.

A shocking ending?
Chris Weidman Vs. Anderson Silva
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Video: YouTube

Event: UFC 162
Date: July 6, 2013

The incredible run of Anderson Silva had fans stunned when Chris Weidman pulled off an upset, knocking him out with brutal punches.

A shocking ending?