Rule number one of inviting a guest on stage: make sure they won't upstage you.
It's clearly not a lesson that Belfast native Jason Clarke has learned yet, because after an hour of tedious, formulaic pop-rock he introduced fellow singer-songwriter Ryan McMullan with the words "prepare to be blown away".
While that may have been stretching things somewhat, McMullan's brief but engrossing performance served to highlight the inadequacies in what we had heard so far. In the sophisticated surroundings of the Merchant Hotel's Roof Garden bar before an audience dressed for a cocktail reception rather than a gig, Clarke ran through his repertoire with the aid of a stripped-down version of his usual band – acoustic guitar, piano and percussion.
He's an accomplished performer with a glint in his eye, but he was let down absolutely by his songwriting, so bland you suspect James Blunt might reject it as insufficiently edgy.
In contrast, McMullan's more bluesy approach overflowed with soul, as well as some nifty work with a loop station.
"He'll be supporting me at every gig until I support him," said Clarke.
Be careful what you wish for.