Taylor Swift and Julia Roberts
Credit: Steve Granitz/WireImage; David Fisher/REX Shutterstock

Taylor Swift's girl squad has grown by two and gained some legendary cred in the process. At the pop singer's Santa Clara, Calif., concert on Saturday, Oscar winner Julia Roberts and folk icon Joan Baez joined her on stage.

"Tonight Julia Roberts and Joan Baez danced it out to 'Style.' These two women are my heroes. What an honor," Swift wrote on her Instagram account. Roberts and Baez are just the latest in a long list of Swift's surprise concert guests, including Kendall Jenner, Karlie Kloss, Cara Delevingne, and Serena Williams.

Taylor Swift The 1989 World Tour Live In Santa Clara - Night 2
Credit: John Medina/LP5/Getty

Julia Roberts and musician Joan Baez united with Swift in Santa Clara, California.

John Medina/LP5/Getty

Swift also brought Brit pop singers Little Mix out on Saturday and performed their hit "Black Magic" with the group. At the rate the singer is collecting awesome woman along her 1989 world tour route, we're half expecting Michelle Obama to "Shake It Off" with her on stage before it's over.