Katy Perry is celebrating another No. 1 as “Dark Horse,” her collaboration with Juicy J, finishes on top this week.

The trap-dance single off PRISM, produced by Dr. Luke and Max Martin, jumps 2-1 on the Billboard Hot 100, and earns Perry her ninth No. 1.

“This No. 1 is the most unexpected one I’ve ever had,” the pop superstar tells Billboard. “‘Dark Horse’ has been a dark horse of a song, since August when the KatyCats voted to release it early on iTunes, before PRISM even came out. I’m so thrilled and grateful to have these moments.”

Juicy J scores his first Hot 100 No. 1. He previously peaked at No. 11 in October as a guest on Mike WiLL Made-It’s “23” featuring Miley Cyrus and Wiz Khalifa.

The Memphis rapper toasted with a bottle of champagne and some Roscoe’s Chicken and Waffles. “Time to celebrate #1 record in the country #darkhorse,” he tweeted.

“Dark Horse” marks Perry’s second No. 1 single off PRISM following “Roar.” She currently ties the Bee Gees, Elton John, a solo Paul McCartney, and Usher for the artist with the 10th most No. 1 singles.