Taylor Swift sang a duet of Alanis Morissette's 1995 classic track, "You Oughta Know" with the singer herself on Swift's 1989 Tour stop in Los Angeles' Staples Center on Monday, according to Time.

Morrissette was the latest guest on the 1989 Tour for the singer from Wyomissing, Pennsylvania.

"She defined the music of her decade," Swift told the crowd, according to Us Magazine. "She inspired a generation of confessional female singer-songwriters who all of a sudden felt like you could actually say these raw feelings that you had. You could actually sing about your real life, you could put detail to it, you could get really, really mad if you wanted to. I think it's fair to say that so many of the female singer-songwriters of my generation, including myself, would not write the way that we do without her and her music. And she has written some of the most brilliant music—in particular probably inarguably the greatest breakup song of all-time."

Ellen DeGeneres and Natalie Maines were also treated to share the stage with Swift as part of a trend she has decided to focus on throughout her journey to promote her new album.