"Nothing against her, but I think when you're doing a tribute to someone that's dead, generally it should be the person's peer," Azalea commented. "Lorde is not Kurt Cobain's peer. No matter if she killed the performance or not, I just don't think it's appropriate."
Given her recent history of diving into spirited debates about the music industry, a rebuttal from Lorde on Azalea's comments would not be surprising.
The Summer of Iggy: Iggy Azalea Cover Photo Shoot
Azalea's "Fancy" (featuring Charli XCX) sits at No. 1 on the Hot 100 for the second straight week. Lorde's debut single, "Royals" topped the Hot 100 for nine weeks in the fourth quarter of 2013.
The Australian-born rapper doesn't mention Joan Jett, St. Vincent or Kim Gordon, all of whom also filled in for Kurt Cobain with drummer Dave Grohl and bassist Krist Novoselic at the ceremony.
Read more about Azalea in this week's cover story, publishing to Billboard.com on Monday morning (June 9). Can't wait? Buy it here.