If the Scottish Cup proved an easing back into domestic life, it will crank up a notch tomorrow night.

Celtic return to league duty at Firhill tomorrow night as they seek to find the kind of form that marked their swashbuckling campaign last term.

The break in sunnier climes might seem like a distant memory given plunging temperatures over the last week but for Celtic it is about re-igniting the fire that scorched all before them in Brendan Rodgers’ inaugural season.

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Saturday’s 5-0 win over Brechin is not the game to judge whether or not the ruthless ease of the Parkhead side is back or not. Certainly, though, there were aspects of the game that would have offered some satisfaction.

The only team without a win in the country were never going to be seen as anything other than

But the glimpse of a livelier Scott Sinclair, who set up the first and scored the second, and the continued oozing of confidence from James Forrest would offer some satisfaction.

Forrest’s opening goal, too, set the tone for an afternoon in which Celtic did what they set out to do. The winger had the ball in the back of the net after just 121 seconds, a goal which came through a sequence of passing moves from kick-off – and culminated with Graeme Smith, the Brechin goalkeeper, being the first visiting player to touch the ball when he bent to retrieve it from the back of the net.

The real stand-out of the afternoon, though, was Olivier Ntcham.

The midfielder ran the show in the middle of the park and the expectation is that the latter half of the campaign is an opportunity for the 21-year-old to really come to the fore. Celtic’s most expensive signing in a decade when he arrived this summer, Ntcham was always going to need time to find full match-fitness after a lack of exposure to regular first-team football.

Having got himself up to speed on that front, Ntcham’s influence can be expected to hold greater sway.

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The only surprise really from there on was the lack of Moussa Dembele on the pitch. With Odsonne Edouard handed the starting jersey the expectation was that Dembele would make an appearance in the second period.

That it didn’t transpire was remarked upon after the game when Rodgers offered his own assessment that the transfer window has proved to be a considerable distraction for the French under-21 internationalist.

The striker’s situation remains something of an enigma for Celtic. Rodgers confirmed after the game that there have been “enquiries” – plural – for the player, but no formal offers – and with just over a week remaining of the week, it will be interesting to see if that interest firms up from the kind of clubs that Dembele himself believes are his next step.

"I don't know [if Moussa Dembele will still be here],” said Rodgers after the game. “Time will tell. He is very much a Celtic player. There has been some interest in him, of course, but nothing official.

"We definitely want to get some more players in before the end of January, to help with the creativity in the team. We certainly want to strengthen.

"It’s just about getting the right type of quality that can improve us – that’s what’s important and that’s never easy.

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"A lot of work has to go in before you do that. We are hoping between now and the end of the month we can do that, and that injection of quality into the team will then serve us well hopefully for the rest of the season."

Leigh Griffiths is expected to be fight for the visit to Firhill tomorrow night as Celtic resume their league campaign. The striker missed the 5-0 win with an ankle injury but came through a training session in the aftermath of the game, with Rodgers confirming that he should be fit to play.

“It was too much of a risk to play him against Brechin but hopefully he’ll be fit for Tuesday,” said the Hoops boss.

The game against Thistle is the first league game since December with Celtic looking to build on the lead at the top.

It will be interesting to see just whether they can keep the fluency shown against Brechin up as they look for a return to league form but the early impressions provided at the weekend will have made for decent viewing.

The lethargy that characterised the December performances ought to have been addressed by the downing of tools although there remains a suspicion that Celtic need the energy of a couple of signings.

Whether they get what they are looking for in this window remains to be seen.