“Ooh, I do like him on that Would I Lie To You?” said the fan from down the road in Blackburn in the bar beforehand.
“But you never know, he might be garbage tonight,” said her husband, as deadpan as you like.
Thankfully for three thousand people packed inside the Opera House, Mack was far from it.
Mack’s Friday night show was a sell-out, like the majority of the Return of the Mack tour which will catapult him into millionaire status (if he’s not already).
With the crowd suitably warmed up by the wonderfully curmudgeonly and hangdog-faced Mike Gunn, Mack bounded on like a man who knows he was about to enter the big league.
His stock has risen by the slapstick fun of prime time slots for TV show Not Going Out, but he has proved himself a sturdy live performer too, ever since his first DVD Live at Bloomsbury Theatre was released seven years ago.
Slim and sharp in a three-piece suit he cast his eye on his latest set of disciples and one ill advised heckle gave Lee Gordon Mackillop, as he was named, his chance to seize the initiative.
Poor Jez on the front row, asking if Mack was deaf, was his fresh meat and boy did he chew him up and spit him out.
The fact he was from Burnley only added to the comedy crucifixion.
Mack tells stories of his life, like the best northern comedians, but it was the way he came up with killer lines in response to the crowd that showed off his true star quality.
A Wiganer who felt the need to clarify his job as a lift engineer by adding “you know....elevators” was putty in the hands of Mack, who left him reeling with his ridicule, not least suggesting there was no buildings in Wigan with more than one floor.
It is this, combined, with his madcap facial expressions (pretending to be a diabetic squirrel with a Snickers bar was brilliant) and constant walking round, which has earned him his sell out status.
His description of the Lancashire accent as having the lethargic pace of a dying battery pack had the crowd in hysterics, as did his bemusement at the spellings of names like Siobhan and Niamh from his recent Irish dates.
But it flagged at times too and you got the impression Mack had to work hard to keep the momentum, falling back to talk about his kids too often to fill in the gaps.
The finale as a magician fell a touch short too. But Mack is a fine purveyor of honest, real life humour and you get the impression living in Surrey among the TV luvvies hasn’t changed him in the slightest.
Let’s hope it doesn’t because his place in the hearts of comedy fans is surely secured.