Enter Rita Regan, a Post Malone fan who got the "Circles" singer ... Though she was happy with Malone's art, she jokes she may have placed the tattoo "differently" had she not been as impressed.

"Let's party, Houston, Texas," he announced before launching into his biggest hits.

Eagle-eyed fans noticed this in the trailer ... She uploaded a photo of the black-and-white cover art for “Fortnight,” which showed Swift and Post Malone sitting together side-by-side and ...

But pop-gone-country singer Post Malone was there to save the day. And during the duo's soaring performance of the 1967 hit, fans would've never guessed that McBryde and Malone had met only ...