Jacare was a heavy favorite, but Rockhold fought toe-to-toe with him for five rounds, and in the end all three judges agreed that Rockhold had won it, with one judge scoring it 50-45 and two others scoring it 48-47.
An emotional Rockhold tried his best to thank all his coaches, training partners and sponsors afterward.
"It's amazing," Rockhold said through tears. "I couldn't do it without everybody -- so many people to thank, so many."
Rockhold was extremely inexperienced going into the fight, with only eight fights on his record, all eight of which were finished in the first round. In fact, Rockhold's 25 minutes in the cage with Jacare represented more fighting time than he had in his entire MMA career prior to Saturday night.
"I won the fight in five rounds," Rockhold said. "I had never been out of the first round."
The fight was almost entirely standing up, with the two of them on the ground for only about half a round of the five-round affair. That played against the strengths of Jacare, a world-class Brazilian jiu jitsu specialist. Rockhold fought the fight he wanted to fight, and he ended it a champion.