I suppose it does not carry much weight when it’s late April and there’s a 12-point chasm between you and your nearest rivals, but for the first time in a long time – Celtic looked a bit sluggish.

This lethargy was apparent to Callum McGregor only during an otherwise forgettable first-half spent toiling to break down an impressively well-drilled Motherwell. Tired of the ball being shuttled sideways in front of 11 claret and amber workhorses, the Parkhead captain decided he was going to lash one at Liam Kelly’s goal, just to see what happened.

Maybe he recognised Celtic’s need to do something different to recapture the attention of a disinterested Parkhead crowd, maybe he was just a bit bored, but either way it skipped off Dan Casey and left Kelly flailing at thin air.

That usually spells the end of the contest at Celtic Park these days.

17 times opposition teams had come to Glasgow’s east end in search of Premiership points this season, and 17 times they failed. Ange Postecoglou has amassed a squad of such depth and quality that going a goal in front tends to have two functions – one being going a goal in front, and the other is daring their visitors to even peek out of their shell in search of an equaliser.

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Accepting the dare generally allows Celtic to step on throats – scoring 103 times in 33 leagues matches is proof they are not for showing mercy. But Motherwell, to their credit, kept faith in what they were doing. McGregor’s goal had an element of fortune about it, and they were not being carved open with any regularity. They also have a wildcard in Kevin van Veen that most teams cannot play at Celtic Park.

The big Dutchman is the archetypal Scottish football cult hero.

Prior to rocking up in Lanarkshire, upon his CV you would find that well-trodden path from Helmond Sport, Djikse Boys and FC Oss, all the way to the bright of lights of Northampton and Scunthorpe. At 31, though, he has found an unlikely, loving home at Fir Park, is a bit of a character, and has the talent to back it up.

Greg Taylor may not fancy watching the striker’s goal back too many times, but Van Veen won’t be letting anyone forget it in a hurry. The Celtic left-back is one of the most diligent, consistent defenders in the league, but he was spun in all directions by Motherwell’s talisman, who then had the wherewithal to anticipate Joe Hart diving low at his feet, lifting a wonderfully composed finish into the Celtic net.

Sometimes when this happens – opponents daring to score a goal at Parkhead – it serves only to make Celtic angry. But their attempts to find a winner felt like the footballing equivalent of trying to shift your car up a gear and it does the horrible jarring thing that vibrates all the way up your arm.

That’s the danger with cruising along in second, even when your destination is in sight, it can be tricky to suddenly transition to top speed.

Tomoki Iwata certainly thought so.

READ MORE: Celtic 1 Motherwell 1 - Champions held to rare home draw by Van Veen moment of class

“I think we made the game difficult by ourselves,” said the midfielder, who looks another fine addition Postecoglou’s squad. “We believe we are putting 100 per cent into every game. Our football is very attractive, I think. 

“We put in 100 per cent and we just try to win the game every time. 

“Personally speaking, I couldn’t get involved as much as I wanted in the attacking situations during the match. I think I have to improve on that in the future. 

“As a team, as I said before, we should have created more chances. Also, from the chances we did create, we should have scored. That’s what I think was missing in comparison with the last few games.”

He was right. Celtic did create a few chances and they tend not to pass them up when a goal is needed, even the ominous addition of seven stoppage time minutes was not enough to break Motherwell’s steely resistance.

With Rangers up next at Hampden on Sunday, perhaps this was a nicely-timed jolt in the arm. Celtic’s consistency has drawn deserved plaudits, but being 12 points clear of your nearest title rivals does significantly dull the sense of jeopardy essential to sustaining the hypervigilance which leads to winning 30 of 33 league matches. Postecoglou has repeatedly stressed that his players’ success is built upon a bedrock of just dealing with the next game, but they are only human and a little drop-off is no great surprise, nor cause for serious alarm.

That being said, the manager will hope weekend absentees Reo Hatate and Jota emerge from a week’s training fit to play. Celtic’s depth of squad, paired with the five substitutes rule, has allowed them to ruthlessly twist the knife on many a wounded opponent, but there is a drop-off when players such as the aforementioned duo are absent simultaneously.

Sead Haksabanovic has served up some sumptuous goals off the bench this season, but he is yet to be overly convincing in the few starts he has made. The winger is a talent, but looked like a player lacking confidence and rhythm on Saturday – he and right-back Alistair Johnston were not always on the same page.

Returning from injury, Aaron Mooy has looked more like the free agent who required patience in getting up to speed early in the campaign, rather than the slipper-wearing playmaker who breezed around as the league’s most in-form player for a period in the New Year. He was poor in the last derby and it would be a surprise to see him start next week.

READ MORE: Ange Postecoglou admits Celtic were 'a bit desperate' against Motherwell

Postecoglou, though, will have been toying with the McGregor-Iwata combination for a reason. The captain has been Celtic’s ever-present anchor, which is also where his Japanese colleague prefers to operate, and it was intriguing to watch them dovetail. Iwata made a noticeable difference when he replaced Mooy against Rangers earlier this month and, with a nickname like ‘the tank’, is unlikely to shy away from the heat of battle.

He has enjoyed them so far – winning helps, obviously – and you suspect he is ready to take on a key role this time around.

“I have played twice in the derby, in the League Cup final and in the league derby here at home,” Iwata said. “There were very good atmospheres in both of the games. Of course, though, it’s very important that we get the result.

“It’s not just about playing in a good atmosphere. Personally, I just need to prepare as well as I can for the next game. I enjoy the pressure because this is something you don’t really get often. 

“But at the same time, I just want to perform well in each game. That’s what I need to do in the following games.”