CELTIC delivered a performance and result which left a lot of people feeling pretty small, chiefly Aberdeen but also those who had speculated that the may be toppled or even taken the distance in a league race this season.

On this evidence green-and-white ribbons may as well be glued to SPFL Premiership trophy. No other team will be champions any time soon. Aberdeen are the one side to have mounted a challenge to in the league and they arrived in Glasgow fancying their chances.

The narrative was that this would be a sluggish, flat Celtic, feeling sorry for themselves after a gruelling European exit in Milan on Thursday night. They would be vulnerable against a fast and substantial force capable of inflicting damage. Well, so much for that. Celtic actually did look a little dormant at first, and might have gone a couple of goals down, until they built a dominant and commanding performance. Aberdeen were quietened and crushed, conceding three goals in a final half-an-hour which became a painful blur.

Trotting out the bare statistics seems meaningless - Celtic are six points ahead, with a game in hand, and a goal difference which is superior by 21 - given that there are no longer any grounds to talk up a credible contest at the top. The second half became a comprehensive exhibition of their strengths and their ability to punish a flailing opponent, even one which retains its status as the best of the rest. Aberdeen folded, defending with untypical naivety and carelessness in the closing stages, and had Celtic been more ruthless the result would have been even more emphatic.

As it was, Jason Denayer's first half goal was supplemented by a Leigh Griffiths penalty when Mark Reynolds made a daft tackle on Stefan Johansen after an hour. Aberdeen played into Celtic's hands after that, pushing forward to chase the game and looking desperate and ragged when they were caught in out of position and overrun. Johansen, Gary Mackay-Steven, Stuart Armstrong and his replacement, John Guidetti, threatened to run riot. One of them would suddenly have possession as an Aberdeen move broke down - Willo Flood became a chief culprit - and they would pour forward on one or two desperate, back-tracking defenders. Mackay-Steven and Johansen helped themselves to goals three and four.

The heaviest defeat of Derek McInnes's reign at Aberdeen eventually deteriorated into a mess, with the sort of defensive chaos which used to be typical of them at Parkhead but had been addressed and rectified since he took over. The victory was all the more impressive given that Celtic were asked early questions by a team which arrived with a gameplan to frustrate and knock them off their stride. Usually Celtic can build from the back through Denayer and Virgil van Dijk. Aberdeen were alive to that and had their quick forwards snapping them down straight away. With Ryan Jack and Flood harassing Nir Bitton and Scott Brown there was no rhythm to the champions.

The opening half an hour was Aberdeen's best spell by far. Niall McGinn tried a terrific, floating shot which Craig Gordon brilliantly pushed over the bar. Andrew Considine put a header over when he should have scored after Kenny McLean returned a Jonny Hayes corner back into the box. Jack hit a shot straight into Gordon's body. At the start, Aberdeen's midfield and forwards were bright and switched on. Even failing to bury a couple of chances need not have deflated them, but then the mistakes began, including a couple of costly ones which put them a goal down against the run of play. Aberdeen put themselves in trouble when goalkeeper Scott Brown collected a pass back and fluffed a kick-out to the feet of Johansen. He laid it off for Griffiths to try a shot which Brown had to parry for a corner, but the danger continued.

Aberdeen lost a winner to a bread-and-butter corner into their goalmouth when Celtic were at Pittodrie in November and it happened again. Stuart Armstrong's delivery found Denayer's head for a simple opener. Jack was angry with Adam Rooney for not doing enough to mark him, but Brown also weakly allowed Griffiths to stand in his way and block his access to the cross. Aberdeen claimed a penalty for a handball by Bitton and Considine had another chance early in the second half but the goal had energised Celtic, who lost Kris Commons to an early hamstring strain.

They grew into the game, taking control of midfield as Jack, Flood, McGinn and McLean, so impressive at first, faded. The movement of Mackay-Steven and Johansen was especially menacing and Aberdeen grew ragged after Griffiths scored his penalty. McGinn was sloppy with a header to Considine in midfield, allowing Adam Matthews to collect and feed Mackay-Steven who scored with a low shot off Brown's hand and the foot of the post.

With ten minutes left, another goal: Matthews burst down the right and cut a low ball back to Johansen whose clipped finish made it 4-0. Hayes had been a surprise starter for Aberdeen because of a hamstring injury only to last barely half an hour because of a calf strain. Aberdeen missed him because he had been tormenting Efe Ambrose, Celtic's surprising choice at left-back. But van Dijk and especially Denayer dealt with anything Aberdeen flung into the box and eventually the threat petered out. Aberdeen were crestfallen.

The league race is a procession for Celtic now and this was the game which finally silenced the strongest of the also-rans.