Amidst performances by country kings like Brad Paisley and Toby Keith, and sparkling songs from boot-wearing queens like Taylor Swift and Miranda Lambert, R&B/pop princess Rihanna waltzed into Las Vegas like she owned the place -- and received quite a warm welcome.

Sugarland's Jennifer Nettles joined Rihanna on stage at the first-ever ACM Fan Jam, and the newly-formed pair gave a jaw-dropping debut performance of the pop star's song 'California King Bed' that shook the roof of the Mandalay Bay and knocked the boots off of ACM viewers.

Rihanna seemed right at home alongside the country starlet, and the fans seemed to think so, too. The crowd erupted in cheers as the performance drew to a close and Nettles gave the newcomer a friendly hug. "It’s the first time that Lady Ri and I have ever sung together and the first time that this song will be performed live so we are thrilled," Nettles said earlier this week. "We’re just big fans of each other. We wanted to do something that was fun and different and fresh, and I reached out to her and said, ‘Hey, anything you want to do?’ and she said, ‘I have this song that I specifically would love to do,’ and I said, ‘Yes ma’am, we will do it.’"

She continued, "It is such a moment. And I think what it shows us is that good music is good and good performance is good, and as long as you like it, who cares what you call it. Get out there and have fun with each other," adding, "I am planning on having a diamond-encrusted crotch."

Unfortunately for viewers, we aren't sure whether Nettles decided to don that diamond-encrusted crotch, as she was wearing pants.

Watch Jennifer Nettles Perform 'California King Bed' With Rihanna at the 2011 ACM Awards