Entertainment Music Taylor Swift Thanks Selena Gomez for Being There 'No Matter What' Following Surprise Onstage Duet Taylor Swift surprised her fans by bringing out one of her best friends to perform a very special duet By Maria Pasquini Maria Pasquini Associate Editor, Human Interest - PEOPLE People Editorial Guidelines Published on May 20, 2018 11:27 AM Share Tweet Pin Email Taylor Swift is pulling out all the stops on her latest tour! Just one day after Swift surprised 60,000 fans at the Rose Bowl in Pasadena, California by bringing out Shawn Mendes, the 28-year-old “Delicate” singer shocked the crowd when she announced she’d be sharing the stage with another very special guest: Selena Gomez. Sharing a behind the scenes look at their rehearsal process on her Instagram Story, Swift and her longtime BFF laughed with each other as they prepared for the big day. “We’re gonna sing ‘Hands to Myself’ which is a[n] absolutely iconic bop,” Swift said, while sharing a sweet moment with Gomez, 25, ahead of the show. “Yes, Taylor loves that one, and I love her for loving it,” Gomez replied. “It’s my favorite song,” Swift insisted. Taylor Swift/Instagram Taylor Swift/Instagram Selena Gomez & Taylor Swift Became Best Friends After They Each Dated a Jonas Brother After sharing a clip of their energetic performance together, Swift wrote a sweet note to her friend on social media. “To the person I could call at any time of day, who has been there no matter what… you absolutely KILLED IT tonight and everyone was so excited to see you. I love you, and 60,000 people at the Rose Bowl loved you too,” she remarked. Want to keep up on the latest from PEOPLE? Sign up for our daily newsletter to get our best stories of the day delivered straight to your inbox. Christopher Polk/TAS18/Getty Images Taylor Swift Opens Up in Emotional Speech About ‘Really Low Times’ While Alluding to Kim Kardashian West Feud on Tour During the actual performance, Gomez also had some kind words to say about her BFF, as she opened up to the crowd about why the pair have remained friends for over a decade. “This person has never ever judged a single decision I’ve made. She’s always met me where I’ve been. She’s encouraged me when I’ve had nothing to be encouraged about, and I don’t know if I would be as strong as I am if I didn’t have you and your family because you’ve changed my life,” she said, according to a video captured by a fan at the concert. But that wasn’t the only special surprise Swift had in store for her fans, which included Julia Roberts, Rebel Wilson, Amber Rose and Bill Nye, on Saturday evening. The 28-year-old also brought out singer Troye Sivan so the pair could perform his hit single “My My My.” Taylor Swift/Instagram Taylor Swift/Instagram Swift’s Reputation Stadium Tour will see her play dates across North America, Europe and Oceania through November.