Marcus North was Man of the Match for his second hundred of the series, Michael Clarke scored more runs than him, and even Stuart Broad and Graeme Swann nearly scored as many but, for me, Ricky Ponting's was the innings of the match - and, arguably, even the innings of the series.

Rightly, batsmen are judged not merely by the number of runs they produce but the quality of those runs. It was clear from the merry romp of England's ninth-wicket pair that batsmen can do plenty of things once the pressure has lifted. With nothing to lose, and nothing to fear, Broad and Swann were able to flay the same bowlers who terrorised their top-order colleagues for two successive days. Ponting, though, switched on his act when the match was still open.

When a Test side gets bowled out for about a hundred runs on the first day, it is natural to assume that the conditions are tilted heavily towards the bowlers. Australia entered the match with a history of weakness against swing bowling. It cost them the series in 2005 and the Test at Lord's this summer, and when the ball swung for one session at Edgbaston they lost seven wickets for 77. In most cases, bowling your opponents out for 102 in the first innings is good enough win a Test, but only if your own batsmen don't perform as badly.

Ponting had gone missing after a big hundred in his first appearance in the series, and the pitch at Cardiff was so benign that only six Australian wickets fell in 180 overs. In the previous innings, when Australia were in danger of losing the Test, he was bowled through the gate by an offspinner, the species that has troubled him throughout his career. And he came to the crease here after Steve Harmison, a man returning to the Ashes battle, had claimed an early wicket with a nasty, steepling ball that Simon Katich was forced to fend off in front his face. The first ball he faced from Harmison zipped through Ponting's bat and his body, not far from the inside edge.

From here, Ponting produced 78 off 101 balls. At one point, he was 32 off 20 balls, with five fours and a six. It was thrilling, counter-attacking batting on a pitch that still had plenty for the bowlers. It can be argued that England bowled poorly to him but often a great batsman in supreme touch can have that effect on bowlers. By the time he was out Australia were ahead by 38 runs and would have had to bat like zombies to lose the Test from there.

As the years roll by, the scorecard will reveal Ponting's contribution as one of the half-centuries in a match Australia utterly dominated. The truth is that it was the defining innings of the match. It had every ingredient that makes a great innings: counter-attack, supreme skills, the purest of strokes, and most of all, coming when it truly mattered.

Sambit Bal is the editor of ESPNcricinfo