Dave Grohl was probably regretting ever mentioning the fact that there was a mystery collaborator on the new Foo Fighters album, considering the feverish speculation and headlines that it generated over the last while.

People assumed that Adele was the artist in question because of her connection to producer Greg Kurstin, but he also had to rule Taylor Swift, Lady Gaga and a number of other pop stars out, claiming that he had made an agreement with said pop star not to mention it.

Now, however, in a new interview with Rolling Stone he has revealed that the pop star in question is none other than.... Justin Timberlake.

He said that they had met while recording in EastWest Studios in LA and "We'd drink whiskey in the parking lot. He was really, really cool," said Grohl. "Then the night before his last day, he says, 'Can I sing on your record? I don't want to push it, but – I just want to be able to tell my friends.'"

Grohl said that Timberlake's contribution was just 'la la la' on one track, but joked that he insisted that he 'nail it'.

The album in question, 'Concrete and Gold', is out next Friday, September 15th.