A freezing fog enveloped Fir Park last night as Celtic found themselves groping in the dark from a game in which their passage had looked straighforward for so long.

A leveller from Danny Johnson just two minutes from time saw Celtic’s chance to go back to the top of the table evaporate; Rangers’ defeat to Aberdeen may well have eased some of the Parkhead side’s frustration but Kilmarnock’s consistency has placed them as leaders of the pack for now.

Having led for much of the game following Ryan Christie’s 13th minute opener, Celtic also had a missed Leigh Griffiths penalty to lament as they tallied up the cost of the draw.

There seemed an inevitability about Christie finding the net given the manner of his performances of late. The playmaker opened the scoring with a strike that is rapidly becoming something of a trademark move as he bore a hole through Motherwell’s defence before unleashing his effort.

For large swathes of this game it looked like it would be sufficient to see Celtic through. The second-half was fairly forgettable although Brendan Rodgers’ will be irked at the manner in which the Parkhead side dominated the game without seeing it properly out.

By the time Motherwell found a foothold in the second period, Celtic should have been well out of sight. Instead, a 1-0 lead is always tenuous and by the time Johnson had the Fir Park side level, the late surge in urgency from the visitors was too little, too late.

Fresh from their League Cup triumph on Sunday, Celtic were keen on ringing the changes for the game. If the personal were different with seven changes to that team, what unfolded initially appeared to stick to a fairly familiar pattern.

Scott Brown was back patrolling the pastures just in front of Celtic’s defence, giving Callum McGregor’s game a more recognisable hue. There would also have been a few peering at the sight of Jonny Hayes, with the former Aberdeen winger making his first start since Celtic’s defeat to Hearts back in August. Olivier Ntcham, Craig Gordon, Jozo Simunovic and Cristian Gamboa were all in too.

Brown’s inclusion from the start was an interesting one. While for some it might point to a restoration of just how it was prior to his injury, the real barometer may well be in the conclusive Europa League game against Salzburg next Thursday night.

The team that starts that game, from which Celtic require a point in order to progress into the latter stages of the tournament, may well offer a genuine indication into the team that Rodgers considers his optimum XI.

Griffiths had the responsibility of leading the line, his first starting jersey since the 6-0 win over St Johnstone at the beginning of October although his hunger for a goal was left unsated. By the time he trudged off midway through the second period he cut a frustrated figure having failed to add to the six goals he has netted so far this season.

The Scotland internationalist had pounced on the ball when Christie had been clumsily upended by Adam Rose in the box. It was a decent penalty from Griffiths but his effort was well saved by Mark Gillespie who dived to his left to beat the ball away at the first attempt before then punching clear the rebound.

It was Celtic’s second miss from the spot in as many games and while it came without cost on Sunday, the same philosophy could not applied to last night.

Stephen Robinson had had to tweak his starting line-up twice in the opening quarter of the game with captain Peter Hartley forced off after just six minutes while right-back Liam Donnelly followed him shortly after.

It didn’t take long for the Fir Park side’s night to get worse again.

As soon as Brown unleashed Kieran Tierney on the flank, Christie was off and running. By the time that Tierney had delivered the ball into the box, Christie had seared his way through the heart of the Fir Park defence. Taking a deft touch with his right foot before unleashing a high left-foot angled effort high into the net, there was an inevitability about Celtic’s man of the moment breaking the deadlock.

It should have been far more comfortable shortly after.

Filip Benkovic thought he had doubled Celtic’s advantage shortly after only to be penalised for a foul while Motherwell struggled to get out of their own half.

Scott Sinclair replaced Ntcham at the break, with the French midfielder looking out of sorts for much of the opening 45 on the left-side of midfield.

Liam Grimshaw had Motherwell’s first effort on target just after the restart and a volley that was deflected wide just after the hour mark but it was a game where they rarely troubled Celtic’s backline.

Odsonne Edouard took over from Griffiths and almost played a part in setting up a goal at the other end. Having gifted the ball to Curtis Main with a slack pass intentioned for Tom Rogic, who had just taken over from the tiring Hayes. That enabled Main to set Conor Sammon through on goal but the striker’s effort lacked any real conviction and was saved with little drama by Gordon.

The same couldn’t be said with just two minutes of regulation time remaining. Johnson capitalised on a long ball into the right channel and angled his effort low past Gordon into the corner of the net.

It sparked a sense of urgency in Celtic’s play for the final minutes of the game - another three were added on - but by then it was gone.