The posters on the programme sellers’ stalls outside Ibrox were prophetic. “The time is now,” they urged. And so it should have proved.
Rangers twice took the lead before seeing their opponents reduced to ten men with over half an hour of the second-half still to play.
Alfredo Morelos, who signed an extension to his contract at the end of last week, missed a chance near the end they will be recalling in Glasgow bars for years to come.
Continuing the theme of question marks on banners over the weekend, the Celtic fans unveiled one at the end.
“Title race? Know your place.” The celebrations of the Celtic players, led by an inspirational Scott Brown, told you everything you needed to know about the significance they were attaching to this win.
The Rangers players, meanwhile, seem to anticipate the sentiment displayed on the banner with their meek response when handed every opportunity to secure three points. Somehow they contrived to come away from a game where they contributed so much, particularly in the first-half, with nothing but regret.
Graeme Murty’s side seemed to wilt amid the expectation heaped on them after Jozo Simunovic’s red card for landing an elbow on Morelos 11 minutes after half-time.
This fixture might seem denuded in the eyes of the wider public. But there wasn’t a game played this weekend containing this amount of drama, intrigue and edge.
Throw in a red card, Celtic skipper Brown dusting down his “The Broonie” celebration and five goals, all of which were excellent, and you have the ingredients for a compelling afternoon.
Modern classic they were suggesting afterwards. The struggle the players had to keep their feet on the heavy turf merely added to the chaos.
Scott Bain, only told on the morning of the game he was definitely playing, was meant to be the nervous debutant. But centre-half Dedryck Boyata, on his 64 th league appearance for Celtic, exhibited all the signs of someone thrown into the deep end as Rangers sought to unsettle the visitors from the off.
So much else happened that even the Bain narrative seemed a little reduced in the end. The goalkeeper did, however, make two fine saves, the second to deny Josh Windass just before Morelos’ latest horror moment in the closing minutes.
The Colombian striker saw his effort from the rebound – and from around six yards out – hit the past and then roll along the line into the grateful Bain’s arms.
He also missed a glaring opportunity from a couple of yards against Ayr United in the Scottish Cup last month. But the consequences were not as grave then.
The intrigue started more than an hour before kick-off with the news Bain was starting for Celtic. It barely let up for the next three hours or so. Dorus De Vries was reported to have turned an ankle in training. So Bain, on- loan from Dundee after being recalled from an on-loan spell at Hibs, was handed his debut in more challenging circumstances than Brendan Rodgers might have wished.
The name of Ian Andrews, who conceded five at Ibrox after being pitched in against Rangers for the first time 30 years ago, could not fail to be evoked. As he saw two goals fly past him before he had even clocked up 30 minutes as a Celtic player, Bain might have feared an Andrews-style experience.
Celtic repelled Rangers’ efforts to get close enough to Bain to test his nerve - for the opening two minutes and twenty seconds at least. But then Boyata dallied on the ball and Windass was quick to rob him of possession. There was still plenty to do for the in-form striker. Windass advanced on Bain before sending a powerful finish into the roof of the net.
The fact Celtic were level after 11 minutes offered some clue as to the kind of afternoon we could expect. Kristoffer Ayer and James Forrest were involved before Tom Rogic received the ball in a position where he’s likely to be of danger. He dragged the ball on to his left foot and curled a delicious shot from 20 yards into the far corner past Wes Foderingham.
The goal was wounding enough for Rangers without David Bates being injured while trying to block the shot. He was stretchered off and replaced by Fabio Cardoso.
Rangers were only briefly put off their stride. A break down the left after Jamie Murphy fed Declan John saw the latter whip over a cross that reached Daniel Candeias at the far post after being missed by the Celtic defence. Candeias shot powerfully into the net via a deflection with Bain helpless.
But Celtic came back again on the stroke of half-time after a sustained spell of pressure. Brown was fouled by Candeias while in the process of making a pass forward to Dembele.
Referee Willie Collum’s decision to let play continue seemed to outfox the Rangers players, with both Cordoso and Foderingham slow to react. Dembele expertly held off the former before expertly hoisting the ball over the latter.
Doubts the game could sustain such relentless pace in the second-half were very quickly erased. Cardoso was booked for a foul on Dembele after 52 minutes and then what seemed likely to prove the decisive moment arrived four minutes later.
Simunovic threw out an injudicious elbow while tussling for possession with Morelos on the near touchline. Collum wasted little time in showing the defender a red card following instruction from near-side assistant, Douglas Ross.
Brown quickly called his remaining teammates around him before heading to the touchline to hear Rodgers’ advice.
This is where the manager, often derided by observers in England for opting to take the easy option in Scotland, earns his corn. He replaced Rogic with Jack Hendry, who filled in at right-back. Ajer moved in one to centre-half. Rangers seemed to run out of ideas.
Then Rodgers, noting how Rangers’ full backs were pushing on in search of a winner, sensed a switch to two strikers could see Celtic profit.
Odsonne Edouard was sent on for Forrest after 67 minutes and within two minutes curled a shot past Foderingham from just inside the box after Dembele’s flick released his strike partner down the left. Rodgers got the reward his adventure merit