At just after 1.30pm yesterday the Kilmarnock team bus pulled up at the grand red-brick entrance of Ibrox.

As Kenny Shiels's team stepped one by one off the bus and through the front door the fans gathered outside – decked out in red, white and blue – began to chant: "We're only here for the Rangers!"

For everyone but the 11 Kilmarnock players on the pitch, plus Shiels and his backroom staff on the sidelines and a small but increasingly vocal group of Kilmarnock fans gathered in the west corner of the Govan Stand, yesterday at Ibrox was always going to be about Rangers. At the end of a week in which the club slid into administration, in which terrible headlines followed dreadful revelations, and with the spectre of liquidation still hovering all too worryingly on the hozizon, this was the first chance for Rangers fans truly to have their say.

What that say amounted to was a mixture of defiance, anger and the odd spot of gallows humour. The Rangers terrace chant, "Follow Follow", was belted out for most of the 90 minutes. More than a few sectarian songs were sung. The National Anthem got an outing and scarves were waved even as Kilmarnock took the lead and the game drifted shapelessly on through a cold blue afternoon at Ibrox. The final result offered no joy at the end of such a dire week for the club – a first-half goal from Kilmarnock and a sending off for Rangers saw the Glasgow team lose 1-0.

Craig Whyte's absence meant that some of the poison of the afternoon had probably been leached away before the game kicked off. Even so, it was there. Across the road from the Bill Struth Stand a raggedly hand-lettered banner screamed "Sold to a Spiv", while in the ground fans in the Govan Stand unveiled a neater but just as pointed message to the last two owners of the club. "Murray and Whyte your sins will not be forgiven or forgotten". Just before 2pm a large group of fans – hundreds, maybe thousands strong – marched up Edmiston Drive carrying anti-Whyte banners.

But the only time Whyte got a mention within the ground outside hushed, urgent conversations about tax bills and PAYE was by the Killie fans indulging in a spot of schadenfreude. "There's only one Craig Whyte," they chanted at regular intervals. "Debatable," the Rangers fan behind me in the Broomloan Stand suggested.

For the home crowd, though, yesterday was not really about apportioning blame. On the front of the Loudon bar a banner hung quoting Ally McCoist. "We don't do walking away," it said. There were more with the same message inside Ibrox. The crowd – in between Follow, Follow and Derry's Walls –adopted the manager's words into a chant: "We don't walk away."

For most of them yesterday was about raging in opposition to the storm that has engulfed their club, and about reiterating their identity, an identity in both its best and worst aspects. Some of the bad old songs were dusted off and sung. Catholics were abused in unmistakeably sectarian language and "No surrender", was belted out at the top of many voices. In the wake of the week's events that latter lyric has acquired a new meaning perhaps, or a new target: HMRC, maybe.

No-one here really believed, though, that Rangers Football Club would disappear. "Scottish football wouldn't exist," fans told each other before the game. "Would you start supporting another team if Rangers go?" I heard one young fan ask his mate. "It isn't going to happen," was the reply.

The only ones contemplating the non-existence of Rangers were the visiting Killie fans. "Soon be a Tesco, this will soon be a Tesco," they chanted gleefully as the game headed towards its end and defeat for Rangers. There was, though, some recognition of the seriousness of the club's situation. Fans before kick-off seriously discussed the prospect of finding themselves in the Third Division. On the train travelling to Glasgow, I heard a couple of teenagers listing what the club could get for the players. "We could get £4 million for Davis," one said to the other. "And then we'll have to rely on the young ones."

On yesterday's display you wonder what the true worth of the current team is. As another Rangers attack ended in a smeary passage of misplaced passes, the guy sitting next to me whistled in frustration. "Scary. And this is before we lose half the team." When the final whistle went, one middle-aged man heading up the stairs in the Broomloan Stand told his mate: "I'm going to go and find my boots in the attic tonight. I might get a game now."

Football fans cleave to the idea that their club is as much an idea as an institution. That Rangers in this case – though Celtic, or Hibs or Hearts or Stenhousemuir fans would say the same – is more than just the team, the club, the board, the bricks and mortar. That it represents something, embodies a vision, a culture, at a push a belief system. It was the idea of Rangers that was being celebrated yesterday. Fans from Wishaw and Deeside, from Ballymena and Lisburn, from Govan and Partick had gathered to say that Rangers belonged to them.

I married into a Rangers family. Not fervent fans but still a family tied to the club through custom and time. I'd hear stories of my wife's uncle who wore a Rangers tie and went to Ibrox almost every week, travelling from Denny to climb Stairwell 13 and stand on the terraces through the 1960s and into the 1970s. He never went to the New Year games, but the possibility that he might have on that dreadful day in January 1971, when 66 people died in a crush, was always there.

That and the club's more familiar successes and failures were constantly graphed during family get-togethers. Rangers FC added colour to lives through the years and down the generations. It was a constant. If there is one emotion that has surfaced more than any other this last week it has been disbelief. How have Rangers come to this?

In a way, yesterday was the easy day for Rangers fans. It might have ended badly on the pitch but the game at Ibrox gave them the opportunity to come together and voice their defiance. The question that will be answered in the days and weeks to come is whether the idea of Rangers is stronger than the economics. On Saturday, standing in a ground full of so many people, so many angry, impassioned, proud people, it is possible to believe.

But the real battle will not be fought on the pitch. "Rangers till I die," the fans chanted as they left Ibrox yesterday. But will Rangers live that long?