The list of musicians on the upcoming Queens of the Stone Age album is getting longer. During last night’s Chelsea Lately program, where Dave Grohl is filling in as guest host this week, Elton John revealed he had recorded with the group.

“Recently, Elton and I recorded something together, something that people wouldn’t imagine the two of us doing together,” explained Grohl to the studio audience.

“Probably not,” chimed Elton John with a playful smirk. “I played on Queens of the Stone Age…”

The pianist explained his rather odd day in the San Fernando Valley. “Engelbert Humperdinck had written me this very sweet letter and asked me to do a duet with him and I couldn’t say no. So I went there and sang with him. Then I drove three blocks and went from Englebert to Queens of the Stone Age, which was a bit of a mind-f***.”

Speaking about Queens, John explained, “I love that band so much and I love Them Crooked Vultures with Josh (Homme)… You know, I played on the last Alice In Chains record,” referring to his work on their 2009 release Black Gives Way To Blue.

John joked that people don’t ask him to play on their records because they think he will say no.

“I remember when you walked in and you said, ‘Alright, what do you have, a ballad for me?,’” recalled Grohl, swiveling his head and rolling his eyes as if a ballad was the last thing John wanted. “Noooo. We don’t have a ballad for you, today, at all.”

John admitted that what was asked of him was very complicated and was in the key of B, “a pianist’s nightmare.”

In addition to Grohl on percussion duties, contributors to the forthcoming Queens of the Stone Age album include Nine Inch Nails’ Trent Reznor, and Scissor Sisters’ singer Jack Shears and bassist Nick Oliveri.

Meanwhile, Elton John will lead a tribute to The Band’s Levon Helm during The GRAMMYs, airing Sunday at 8 p.m. on CBS.

– Jay Tilles, CBS Local