They certainly had not turned up for the first half. Indeed, they appeared as a substantive force with only minutes of this compelling contest left.
There may be two reasons for this lack of visibility. First, there was Celtic's contraction of the virus that has afflicted them on visits to Inverness, in Scottish Communities League Cup finals and on the odd, very odd, trip to Rugby Park. This ailment produces a listlessness that is characterised by a lack of commitment and punished by defeat. It is hard to predict. Celtic, after all, have performed powerfully at Ibrox on occasion, most notably in last season's Scottish Cup tie.
Second, Rangers adhered to the Old Firm truth – evident to all veteran spectators of this match – that the team labelled as underdogs can have a ferocious bite. This is known as the Dr Jo theory in memory of Venglos of said denomination who led a Celtic side to a 5-1 win over what was perceived to be a hugely superior Rangers managed by Dick Advocaat.
This, then, was a match of three red cards, five goals and a manager sent to the stand. It was routine Old Firm. Only occasional observers would have been surprised by the tumult off the park and the controversy caused by events on it.
The result, though, may require some explanation to those who make wagers using form and looked at a Rangers side falling to regular defeat and Celtic racking up an impressive 21-match unbeaten run in the Clydesdale Bank Premier League.
So what happened? It may be best to deal first with the champions elect. Apart from Fraser Forster, this was a side that slid towards defeat with token resistance until it seemed to realise that the mass of support behind goal deserved some gesture of defiance. The goalkeeper could not be blamed for any of the goals and made some decent saves but what were the Celtic fans to make of the rest of the team?
A strong case could be made for Kris Commons as being Celtic's perkiest outfield player and the Scotland internationalist ventured on to the pitch after 70 minutes. There was a flurry after Rangers scored their opening goal but, with a league still to be won, Celtic were tentative for most of this match before their extraordinary revival that pulled two goals back from the brink of the rout. There was no consolation in this, though, only the realisation that a degree of focus could have made this a much more difficult match for Rangers.
This was a straightforward victory for the champions, despite the flurry of goals and the waving of red cards. The dismissal of Cha Du-Ri could be construed as harsh but Calum Murray was within his rights to send off the South Korean. The red card for Victor Wanyama was routine, with the Kenyan guilty of a reckless challenge.
But Rangers merited the win for a performance of some conviction. Ally McCoist, the Rangers manager, was predictably positive, with Lee McCulloch placed as point man and Sone Aluko charged with joining him and exploiting the space in front of the Celtic back four. McCoist's selection of a back three allowed Lee Wallace and Steven Whittaker to push forward. The first did this to some effect, drawing the foul for which Cha was sent off and scoring what proved to be the winner. The latter produced the cross for the second goal.
Aluko, who scored a marvellous goal, won the man-of-the-match award. Rhys McCabe also made excellent use of the ball.
However, the most influential performance came from McCulloch. At one point in the first half, he drifted wide, held his arm aloft and the ball was pinged across to him. He, of course, won the header, directing it towards Aluko again. It was emblematic of his match.
As this contest progressed and three players were invited to use the showers prematurely, McCulloch slid back from being the main striker, to a holding position in midfield and then to a place in the back four. McCulloch, now 33, was once Walter Smith's choice to bully the full-back on diagonal crosses. Yesterday, he imposed himself on Celtic's back four, giving a platform for Aluko to cause irritation and for the wide players to foray forward.
McCoist will accept that it is the players who prevail, not tactics. But he set up his side with some wit. The back three could have been exploited, but the positioning of McCabe and the experience of the rest of his squad ensured this was an afternoon when Allan McGregor was forced into fine saves just twice.
The Rangers goalkeeper picked the ball out of his net on two occasions late on as Celtic found a belated verve. By this time, Lennon was in the media room watching the match on television. The afternoon had passed him by at a distance. It may be a feeling shared by his players.