Jethro Tull frontman Ian Anderson has said he would happily collaborate with Metallica if the opportunity arose, describing the prospect of adding his trademark flute to a track by the thrash metal giants as an appealing challenge. The comment revisits one of rock's more unusual footnotes: Jethro Tull's win of the first-ever Grammy for Best Metal Performance in 1989, awarded for the album "Crest of a Knave", controversially beating Metallica despite Tull bearing little resemblance to a metal act.

Rather than souring relations, the surprise result reportedly helped forge an enduring, good-humoured rapport between the two bands. Anderson explained that he has previously worked with several hard rock and metal acts, relishing the challenge as a flautist, and said that if Metallica sent him a rough mix and asked where to place his flute, his answer would simply be yes. The article notes such a pairing would mark a departure for Metallica, who rarely repeat past formulas, and draws comparisons to Tony Iommi's flute work with Black Sabbath as a precedent for unexpected woodwind additions to heavier music.