By Hilary Whiteman, CNN
Updated 2:20 AM ET, Sun November 15, 2015
Holly Holm lays into Ronda Rousey during their UFC women's bantamweight championship bout during the UFC 193 event at Etihad Stadium on November 15, 2015 in Melbourne, Australia.
Story highlights
- Ronda Rousey loses fight to rival at event in Australia
- Kick in second round sent Rousey tumbling
- Holly Holm is new world bantamweight champion
(CNN)In possibly the biggest upset in UFC history, Holly Holm has knocked out Ronda Rousey, the woman who claimed to be "the best fighter in the whole world."
The fight-ending kick came 57 seconds into the second round, striking reigning women's bantamweight champion Rousey in the neck and sending her tumbling to the floor.
Rousey's early exit saw Holm, a former professional boxer turned mixed martial artist, take the bantamweight title at the main event in Melbourne, Australia.
Ronda Rousey receives medical treatment after being defeated by Holly Holm on November 15.
The shocking loss has ended Rousey's impressive run of 12 victories, some of which occurred within seconds of entering the ring.
In August, the 28-year-old fighter knocked out Brazilian Bethe Correia in just 34 seconds. It took even less time for her to dispatch rival Cat Zingano in February.
