Some days have greatness thrust upon them. Yesterday was one of them, although the day itself did its best to resist. The rain softened the Croke Park pitch up all week long, robbing the sprites of either team of a yard of pace. The stadium was two-thirds full and neither contingent of supporters travelled with unsullied optimism. And yet, and yet. Hurling rose above it. Cork and Offaly delivered a game of splendour. Cork marched onto the All-Ireland final.

This was an All-Ireland semi-final which many saw as a stodgy appetiser to next Sunday's fare. Instead Cork's advance to their first final in seven years was made possible only by their resilience in an extraordinary game, the narrative of which was unpunctuated by goals or distinct turning points. It was a game which simply ebbed and flowed and if for much of it Offaly looked to have the more confident stroke, the bursts of enthusiasm and inspiration which Cork periodically summoned up were enough for them to prevail.

Through the first half Offaly produced much of the nonchalant genius for which we celebrate them. Cork, huffing and puffing and looking for some sort of opening by which they might insert daylight between themselves and the All-Ireland champions, couldn't even establish a lead.

Every time they shuffled and danced and worked out a way to land a punch, Offaly would just slap them on the nose by way of return. Joe Deane levelled the scores. Michael Duignan instantly restored Offaly's lead. Seanie McGrath pointed. Joe Dooley put it over almost from the puck out, and so on. Another Deane point instantly negated by Johnny Dooley.

It was one of those days we waited for Offaly to cut loose and kill the game dead. Instead, two injury-time points in the first half, both of them from Deane frees, put Cork just a point off Offaly at half-time. They had reason to be thankful that they were allowed to breathe down Offaly's necks: they had done less hurling than their counterparts.

After the break they blossomed, rifling over four points in unbroken sequence to establish a lead which, although it would be surrendered and regained before the half was out, served as a stiffener for their confidence.

The second half was a hayride, a rollercoaster whirl which deserved an audience larger than the 37,629 who saw it. Offaly, surprised perhaps at the impertinence of Jimmy Barry-Murphy's young team, swarmed back, picking three points of their own before Deane had another Cork free which prompted Offaly to another three points and a two-point lead to nurse through the last 10 minutes.

The game grew and unlikely heroes were found. Kevin Murray thieved a lovely point which revived Cork like a dose of smelling salts. John Troy was penalised for a pick-up which he hotly denied and Cork were level.

Offaly's hurling was still fluent and with Johnny Pilkinton having moved his bundle of talents into the full forward position, Croke Park braced itself for another of Offaly's late plundering jobs. Instead Ben O'Connor, who with a Cantona-like flourish of arrogance only chooses to score points if they are sublime points, put Cork ahead.

The stadium was breathless now. Collectively struggling for breath or words. Seanie McGrath almost has a goal for Cork . . . Offaly lose control at the other end . . . Cork add a point . . . Paudie Mulhare is denied a goal at the other end . . . Deane caps Cork's day . . . Offaly must score a goal . . . Dickie Murphy blows the long whistle and spreads his arms wide. Offaly collapse in a shellshocked heap of regret.

Cork's young team thus accessed an All-Ireland final which seemed hopelessly beyond their grasp when Jimmy BarryMurphy picked a team with six debutants to play Waterford earlier this summer. Barry-Murphy has known growing pains as a manager, but this team moves with a lightness and confidence which has spared them similar hardship.

For Offaly there was a sense of an era closing. It was summed up most poignantly by Brian Whelahan, who is undoubtedly the greatest hurler the county has produced. He sat in the dressingroom afterwards, shampoo suds capping his ears and sadness misting his eyes. Nobody has been more integral to the last 10 years of the Offaly story than Whelahan. On good days he's been at the heart of it. On bad he has been the one to look forward again. Yesterday he seemed defeated.

"I'm delighted that the team hurled well," he said. "We were given no credit. We put on a makeshift performance against Wexford, then conceded five goals against Kilkenny, then Antrim proved to be of no use to us. I'm just delighted we played well."

Offaly, without a minor win in Leinster this decade and with their hurling schools in decline, face a bleak future. The generation which followed the 1981 breakthrough team haven't been replaced. Now they themselves are looking at retirement.

"If the team breaks up, it breaks up, but at least after putting in a good performance," said Whelahan. "Offaly hurling speaks for itself. I hope everyone who has written or put Offaly down over the last year will have a strong think about it. We've only been around the last 20 years, but we've given great memories. I hope it's not going to be a hundred years again before we see Offaly in an All-Ireland series.

"We're going a long, long time. You can't keep going year after year. We tried our best to get everyone back for this year, we were All-Ireland champions so a lot of lads came back to see if we could do it back-to-back."

Cork people were still celebrating outside. The sense of one era ending and another just beginning was as palpable as at any coronation.