Neil Young performs onstage at the 25th anniversary MusiCares 2015 Person Of The Year Gala honoring Bob Dylan at the Los Angeles Convention Center on Feb. 6, 2015 in Los Angeles.

Neil Young has been forced to pull out of inducting Pearl Jam into the Rock and Roll Hall of Fame this Friday (Apr. 7) due to an undisclosed illness.

The Rock Hall made the announcement on Wednesday (Apr. 5), revealing that retired late night talk show host David Letterman has agreed to take Young's place.

Due to illness, Neil Young is sadly unable to induct @PearlJam @ this year's ceremony. We're thrilled David Letterman has agreed to step in. pic.twitter.com/7k463ajhV3 — Rock Hall (@rockhall) April 5, 2017

A spokesperson for Young could not be reached for comment on the rock icon's health. Young and PJ have had a decades-long friendship and working partnership, with the super-combo memorably joining forces to play Young's "Rockin' in the Free World" at the 1993 MTV Video Music Awards. PJ regularly cover the song on tour and members of the group played on Young's 1995 album Mirror Ball.

This year's ceremony will take place in New York and will feature Jackson Browne inducting folk legend Joan Baez, and Geddy Lee and Alex Lifeson of Rush ushering in progressive rockers Yes. Presenters for other inductees Tupac Shakur, ELO, Journey and Nile Rodgers haven't been announced, though former labelmate Snoop Dogg will induct Shakur.