The 31-year-old, comfortably the pre-eminent player in the SPFL Premiership this season, comprehensively consolidated those credentials with a second-half hat trick which took him on to 26 for the season and allowed Celtic to savour the Friday night feeling down in Ayrshire.
As well as currently appearing a shoe-in for the golden boot - 21 of his goals have come in the league - this was the kind of performance which threatens to make the freshly-launched PFA Scotland player of the year vote seem about as meaningful a contest as a Zimbabwean general election. On the subject of one-horse races, the result also leaves Celtic three wins away from a third successive title, making March 29 against Ross County the latest potentially decisive date in the diary.
Commons is a gift which keeps on giving. While Celtic have an option on the player's services for at least one more year, Neil Lennon has spoken of persuading him to remain at the club for the remainder of his career, even co-opting him onto the club's backroom staff when he retires. With a young family up the road, the player is settled in Scotland but on this evidence he is entitled to charge a premium in his negotiations.
Rather than a perfect hat trick, all three of the 31-year-old's goals yesterday were delivered with that devilish left foot. The first, as we approached the hour mark at a chilly Rugby Park, saw him work a one-two with Leigh Griffiths, before flicking the ball unerringly across the face of Craig Samson with the outside of his boot. The second, which arrived seconds later, was simpler, as he funnelled the ball wide for the rampaging Adam Matthews, then timed his arrival perfectly to sidefoot in from close range. He even had time to have a goal ruled off for offside before lashing in a third, from fully 20 yards out, into the bottom corner.
With a third successive title imminent, Neil Lennon had spoken pre-match about blooding a few of his younger players, and true to his word there was a first competitive start here for 17-year-old Liam Henderson. The Scotland under-19 player is versatile enough to be accommodated in a number of positions but last night he joined Scott Brown and Stefan Johansen in a three-man midfield, with Charlie Mulgrew slipping seamlessly into the central defensive role vacated by Virgil van Dijk, who was serving his suspension for the red card he picked up at Pittodrie. He did fine, as did the callow Kilmarnock central midfield pairing of Mark O'Hara and Craig Slater he was up against, with Swede David Moberg Karlsson, Michael Gardyne and the impressive Rory McKenzie tasked with providing the service for Kris Boyd, who was barracked remorselessly by the visiting support.
Griffiths was allowed to continue his burgeoning partnership with Anthony Stokes up front, and it was the Irishman on the end of the game's first chance, locating the net following a Commons flick only to see his effort ruled out for offside. But for much of the first half, despite the best efforts of the players, the two sides cancelled each other out.
Gardyne shot wide, then a Sean Clohessy cross caused brief apoplexy in the visitors' defence at one end, while Griffiths and Commons both tested Craig Samson at the other, but the closest we came to a goal at either side came when Samson spared Lee Ashcroft's blushes after some great work from Matthews.
Celtic emerged after the restart with a collective flea in their ear. Johansen tested Samson with a drive from long range, then Efe Ambrose headed wide from the resultant corner before Commons struck.
As for Kilmarnock, there was an enterprising cameo from Chris Johnston - the long-haired youngster should at least have grabbed a consolation - and further good news for most of the Rugby Park regulars resided in the form of the boardroom movements which saw controversial chairman Michael Johnston agreeing to step down at the end of the season, as part of a deal which will allow the club to clear their £9m debt.
Celtic's previous Friday night football experience this season saw a whopping win at Motherwell negated somewhat by the behaviour of a travelling support who let off flares and damaged seats, but apart from one green smoke bomb which greeted the opener, thankfully the pyrotechnics were largely confined to the field.