Inside the stadium, the songstress documented the action from her ringside seat, sharing video with Rockhold -- and even a quick glimpse of BFF Nick Jonas! -- to her Instagram story. Plenty of other famous faces were in attendance as well, including Madonna, Zac Efron, Hugh Jackman, and Joan Smalls.
Though this was the first time we've seen PDA from the pair, this wasn't their first public appearance. Just last week, they took in the Los Angeles Rams' home game against the Carolina Panthers at the LA Memorial Coliseum.
Over the summer, both also dropped hints about their relationship via Instagram, sharing photos of their matching pinky finger tattoos.
"Cause life's too short not to tattoo your pinky," the 24-year-old captioned her snap from August.
Three days earlier, the 32-year-old UFC champ posted a pic of his own pinky with the same smiley face tat over a serene ocean scene.
ET has reached out to Lovato's reps about the relationship.