Superstar collaborations can be very messy affairs, egos audibly jostling in front of the mikes for available space but this one - and no surprise, in truth - is a fine example of two musicians at the peak of their craft coming together in a celebration of the blues. I hadn't realised it, but it's the first time they've combined as front line artists and all the fresher for that.

They open with a spare enough reworking of the John Hiatt title track and slide and shuffle through classic upon classic, with King's own 'Three O'Clock Blues', at over eight minutes long being an object lesson in how to have fun and still not waste a note.

Former Crusader Joe Sample is in particularly good form on piano here (and throughout) and King and Clapton's guitars simmer in low heat during 'Help The Poor' until the coda lets them really show what they can do.

A long time in coming, this album is neither going to change opinions nor lives. It is what it is, a classy uncomplicated workout between two friends and a strong supporting cast. That said, it's an album I'll come back to again and again, because all told, music really doesn't come much better than this.