THE debate about disparity in football can safely rumble on for a bit longer yet. Five days after being belittled by the giants of Paris Saint-Germain in the Champions League, Celtic returned to Lilliput yesterday and made Ross County feel tiny.

Just as Brendan Rodgers and his players continue to puzzle over just how they can close the gap on the European elite, so must the rest of Scottish football agonise over an inability to land a telling blow on the champions. This was a 55th domestic game unbeaten for Celtic and with each passing week the prospect of another flawless season grows increasingly possible. Had they scored a fifth goal without reply – as they threatened to in the closing stages – then that feeling of symmetry would have been even more striking.

In the end, Celtic settled for just the four in a performance that ticked along nicely without ever veering towards the spectacular. County had one or two chances but beyond that it was as one-sided a contest as it had been in midweek. The only major difference was the atmosphere, Celtic Park as subdued as it had been frenetic ahead of the visit of Neymar, Edinson Cavani and the rest.

The headline news on the occasion of an otherwise fairly humdrum Celtic victory was the return of Moussa Dembele from injury after a two-month lay-off. Partnering, rather than replacing, Leigh Griffiths in attack as Rodgers rolled out a 3-1-4-2 formation, the Frenchman looked understandably rusty at times but still had the presence to score his first goal in six months, Celtic’s second of the match.

Arriving just three minutes before half-time and with Celtic already coasting, it was a smart finish from Dembele low across goalkeeper Aaron McCarey after Griffiths had laid the ball off to him. The Frenchman was taken off after an hour – Rodgers had said beforehand the striker wouldn’t go the distance – and will likely be given further minutes in the Betfred Cup against Dundee in midweek ahead of a possible start at Ibrox in the derby next Saturday.

“[His goal] is great for confidence and I thought that those two boys linked up very well,” said Rodgers. “We’ll see what his reaction is after [his injuries] this year. We don’t really need the hamstring going again so we don’t have to force him in.

“We have a really good squad of players, young Odsonne [Edouard], Leigh and others who can play there. So that was the reason for bringing in the third striker. Moussa and Leigh have an injury history so we don’t really want to push it unless we have to.”

Dembele’s goal gave Celtic a comfortable cushion, but any chance of a County upset had effectively evaporated when they fell behind after just 13 minutes. It was a crisp strike from Tom Rogic, McCarey seemingly befuddled or unsighted as the ball skirted past the leg of defender Kenny van der Weg on its way to goal.

It made the second half effectively a non-contest, any prospect of a shock all but gone. Celtic scored a third after 52 minutes when Rogic had another pop that was parried by the goalkeeper but only into the path of James Forrest who knocked the rebound into the net.

Celtic weren’t finished there and Forrest rubbed further salt into County wounds with a fourth goal after 74 minutes, cutting in on to his left foot and fizzing a driven effort into the corner of the net. Substitute Scott Sinclair had the best chance to add a fifth – McCarey made a smart stop from close range – but, regardless, this was an accomplished if perfunctory performance from Celtic.

“It was perfect,” purred Rodgers. “The players deserve a huge amount of credit. To come into a game after the midweek game, with a lot of energy put into that, we knew we were going to play against a Ross County team that are very dogged and would make it difficult for us. We said to the players, 'listen, we take our medicine during the week and we learn from it’. And that is what this group are very good at doing.

“We play teams four to six teams a year and Celtic always has to be dominant. But it can never be stale. You can’t be predictable. And having the flexibility to play in the different systems that we do will hopefully make it challenging for our opponents each time we play.”

County’s season won’t be measured by games like these although they may harbour regrets ovfer missing decent chances when the match was still within their reach.

At 1-0, Alex Schalk should have got a lot more power on his shot after latching on to Ross Draper’s pass, while Craig Gordon was finally called upon to earn his corn early in the second half when he denied first Craig Curran and then Davis Keillor-Dunn with smart stops in quick succession. Celtic promptly went up the pitch and knocked in their third, much to manager Jim McIntyre’s frustration.

“The bottom line is we won’t be judged on what we do against Celtic but we still want to be better than what we were today,” he said. “They are expected to win games at home against Ross County but I expect my team to be more in their face than what we were in the first half certainly.”