Watch Nelly Perform With Taylor Swift

The highlight of our friendship thus far @HAIMtheband PS WE LOVE YOU @Nelly_Mo #1989TourStLouis pic.twitter.com/3USBBookRg

— Taylor Swift (@taylorswift13) September 30, 2015

Taylor Swift's 1989 Tour has quickly become famous for the headliner's numerous--and often surprising--guest performances. Recently, she brought out Mick Jagger to sing the Rolling Stones' "(I Can't Get No) Satisfaction"; in Seattle, she brought out Ciara and Russell Wilson, presumably ending her relationship with the Dungeon Family forever. But last night (Sept. 29) in St. Louis, the Pennsylvania-born singer brought out a man whose ear for pop once rivaled hers. Nelly hit the Scottrade Arena stage with Swift to perform his latest single, the Jeremih-featuring, Mike Free- and DJ Mustard-helmed "Sexual Healing" rework "The Fix" and his 2002 classic "Hot in Herre." See performance of the latter both above and below, and try to process the fact that the women of Haim also served as backup dancers. No word on whether "Tip Drill" was played at the after party.

After more than a decade at the top of rap's commercial power structures, Nelly recently decided to strike out on his own. (Check out the MC's XXL interview for more on that.) Despite waning sales, he's managed to keep his name in the press and hopes to secure a release date for his forthcoming eighth solo album. For her part, Swift continues to be so popular as to count as an anachronism: adjusting for the deflated record industry, her last three albums are among the fastest-selling since Soundscan's inception.