The 25-year-old entertainer looked like she was having a blast, and was later seen drinking Diet Coke backstage.
“Thank you so much @BigSean for coming down to perform with me at the last minute tonight! What a guy 🙏 #WangoTango,” Calvin tweeted.
In case you missed them, Taylor has been slowly releasing promo posters for her upcoming “Bad Blood” music video! Check out the ones so far for Ellie Goulding, Zendaya, Gigi Hadid, Lily Aldridge, and Hayley Williams!