The performance was so good that UFC President Dana White made it a point to give the band some free publicity in media interviews late last year.
"I've been working on the Red Hot Chili Peppers for two years," White said. "First of all, they've never done anything like that in the history of the band. I got Flea and Anthony [Kiedis] to get together to figure this thing out and they did. Let me tell you what: They came in there ... it was the most amazing setting -- the room was smaller than this -- and they played like they were playing for 20,000 people. It was awesome.
"I've been a huge fan of the Peppers since I was a kid. As you start to meet people you've admire or someone who is a celebrity, it's really cool when you meet somebody who you admire who is worth admiring. And they are those type of guys -- they are the nicest, most down-to-Earth, respectful, amazing human beings you will ever meet. And when I say human beings, they are amazing human beings. They do lots of things for other people, they care about other people."
This holiday season, Kiedis turned the tables by giving the UFC some props during his media interviews.
"Honestly I have about 10,000 UFC memories because I watch it religiously," Kiedis told UFC.com reporter Megan Olivi during the UFC on Fox 9 event.
"In a word, I'm impressed," Kiedis said when asked what he thinks about the evolution of the sport. "It's almost like the longer it goes, the faster is evolves. I don't know, that's the exciting part."
Kiedis went on to say that some of his favorite fighters are Cain Velasquez and Frankie Edgar.