You see it in fighters when they know they are in danger of losing it all in the ring and fear they have gone into a situation they maybe no longer control, not, certainly with the old swaggering belief in their powers.
The greatest of them, though, resolve that, however heavily stacked the odds, they will leave some of the best of themselves. They will not go with a shrug of resignation.
You see it in so many fighters, particularly, and in the last few days here you see quite a lot of it in Ricky Ponting – and this was never more so than early this morning when he fell first ball to Jimmy Anderson, the fifth golden duck of his career, and wondered if indeed the glory was just about over. It did not help that he had to sit along the two other victims of England's instant assault : Simon Katich and Michael Clarke.
You see a captain of Australia calling up a belief that if the days have lost so much of their promise, if he no longer has guarantees that certain players can deliver something vital when it matters most, no more than he can trust hook and pull shots that not so long ago were glories of cricket, he might just find a way to hold back the moment he has been dreading.
Ever since, no doubt, team-mates like Glenn McGrath, Shane Warne, Adam Gilchrist and Matthew Hayden announced that their days were done.
Ponting, at 35, refused to believe that he was fighting history almost as much as England through the small hours of this morning on the first day of the second Test.
However oppressive the evidence coming in, the Australian captain declines, quite ferociously at times, to admit he is involved in something that might be described as Ponting's Last Stand.
But everyone knows he is, and perhaps not least Ponting himself. For confirmation it is necessary only to see him walking, rapt in his thoughts, in the downtown streets near the beautiful Adelaide Oval or scurrying down a corridor of the team hotel, to know that this, maybe for the last time in a brilliant career, is a man utterly possessed by a single challenge.
There was fresh evidence of the encirclement of Ponting coming into this Test. One newspaper pronounced the man who has scored 39 Test centuries and led Australia to years of dominance "clueless".
There were also stories, pointedly not dismissed by the captain, that his old influence in the selectors' room had declined, along with three straight Test defeats, with the failure to put England to the sword after winning a huge first-innings advantage in the first Test. There is also the possibility that he will lose three Ashes series.
Ponting, it seems clear, fought hard against the dropping of the crisis-ridden fast bowler Mitchell Johnson but, unlike so many times in the past, his argument was heard but not accepted.
"Sometimes," he said, "it doesn't matter what I think. We thought long and hard about the decision that was made with Mitch. We honestly thought it would make our attack better for this game. When it's a big decision it is wholly and solely made by the selection panel. Of course they ask for my input and the coach's, but they make the decision."
He was candid enough when asked if maybe Johnson had been entitled to the kind of patience that was granted to Mike Hussey, Australia's batting hero at The Gabba. "A good question," said Ponting, adding, "You might have to ask Andrew Hilditch [the chairman of selectors] about that."
Yet in every flourish of body language, Ponting defies the theory that both he and his nation's cricket have rarely been so embattled. "There is no greater satisfaction in the game," he says, "than to find a way of winning when everyone is telling you that it's just not possible."
Ponting wants this redemption after last year's Ashes loss in England – and the all-pervading sense that in the second-innings total of 517 for 1 achieved by his opponents at The Gabba last weekend an unbreakable psychological edge was created – so badly it has become not so much a compelling aspect of the unfolding series but one man's fight to hang on to his identity.
It is a profile that has been built down the years by both extraordinary batsmanship and will, and was first sketched by Ponting's great predecessor Steve Waugh.
Waugh fought, sometimes to the point of ridicule, to preserve the image and the ethos of the Australian cricketer. He took his players to old battlegrounds in the Crimea, he insisted the baggy green cap was a symbol of more than mere patriotism but a way of thinking and fighting and never conceding an inch.
And he knew that, after some youthful turbulence, Ponting had consumed the message whole.
When his protégé was appointed captain in his place, Waugh declared: "Ricky Ponting was destined to lead his country. I couldn't have handed Australia's ultimate individual honour to a more capable and deserving man. A captain must earn respect by leading on all fronts, 'Punter' has undoubtedly excelled. My advice to him is to look after his own game, maintain his form and everything will flow from that. He has elevated his hunger and desire for runs to a level that most can only aspire to."
You thought of all that ambition smoothed into a superb career on the days before this Test when he scoured the nets to see signs of difficulty or crisis in any of his team-mates and at one point broke off from his own work to help his vice-captain, Michael Clarke, on some critical problems in a once-superior technique.
It was not the least irony of their swift returns to the dressing room this morning. "We still have everything to fight for," he said before his latest blow. That's what all the fighters say. Some of them mean it, however, and in that number only a very foolish opponent would forget to put Ricky Ponting. This was still true in the shellfire that engulfed him this morning.