The biggest turning point of the greatest cricket series ever played came during a game of rugby. Australia were warming up on the morning of the second Test at Edgbaston, playing touch rugby, when Glenn McGrath trod on a stray cricket ball and badly injured his ankle. As word spread that McGrath would miss the match, the whole of England celebrated like a dictator had been overthrown.

Although the pitch looked good, Australia had planned to bowl first if they won the toss in an attempt to further expose the wounds opened by McGrath at Lord's. In his absence, Ricky Ponting took the same decision to the surprise of almost everybody at the ground. The video of the toss shows his opposite number Michael Vaughan having to work exceptionally hard to retain his poker face at the moment Ponting says Australia will bowl. "He's a lovely guy, that Ricky Ponting," said Geoffrey Boycott later. "He likes the English so much he changed the series with the most stupid decision he'll ever make in his life."

Normally a captain is savaged if he bowls first and a side makes 600. England made 407 at Edgbaston, a good score but no more, yet the manner in which they did so changed the mood of the series. They scored those runs in just 79.2 overs, at a staggering 5.13 per over, with 10 sixes. It was an outrageously aggressive response to the crushing humiliation of Lord's.

Marcus Trescothick set the tone with a coruscating 90, and after lunch Kevin Pietersen andAndrew Flintoff had a game of unspoken one-upmanship during a partnership of 103. Pietersen made 71 and Flintoff returned to form with 68 from just 62 balls. That included five sixes, one hooked blind off Brett Lee, an unwitting homage to Ian Botham in 1981. Flintoff said he bottled it at Lord's; if he could have bottled the freedom with which he played for the rest of the series, he would have been one of the greatest players of all time.

In the most important game of their lives, England batted with happy abandon. It was their captain Vaughan who imbued the entire side with the same aggressive approach he demonstrated in Australia in 2002-03. "He's the best liar I ever met," said Steve Harmison of Vaughan's ability to make his team believe everything was or was going to be okay.

He didn't need to lie on the second day, as England took a significant first-innings lead of 99. Giles' dismissal of Ponting - who moved ominously to 61, determined to make up for his decision at the toss - was a key moment, one of three important top-order wickets for a player who had been heavily criticised after the first Test.

Any sense of English comfort soon started to dissipate, however. Warne bowled Andrew Strauss with a staggering delivery on the Friday evening - his Ball of the Twenty-First Century. On the eve of the match, Warne was asked about his famous delivery to Mike Gatting in 1993. "I'd give up sex to bowl a few more of those balls this summer, that's for sure." The delivery to Strauss, and the grainy pictures of Warne in a hotel room with two blondes and an inflatable, suggested there was no need for such a trade-off.

On the third morning at Edgbaston, Warne and Brett Lee reduced a jittery England to 75 for six. Flintoff then continued his exceptional match with 73 from 86 balls, including four more sixes. The third, a bunt down the ground off Lee provided one of Mark Nicholas's many memorable commentaries during the series on Channel 4 in England. "Oh, hello! Massive! MASSIVE!" All the while his co-commentator Boycott could be heard cackling with disbelief and joy. Flintoff added 51 for the last wicket with Simon Jones. Warne, bowling imperiously, ended with six for 46 in the innings and ten in the match. As Flintoff walked off, Warne shouted after him. When Flintoff turned round, Warne mouthed "well played" and applauded.

Australia were left needing 282 to win. Matthew Hayden and Justin Langer moved so easily to 47 for none that, even at that early stage, it felt like it was Flintoff or bust. In his first over, he dismissed both Langer and Ponting. It was the moment an ordinary human being became SuperFred. Langer was bowled off his elbow, and then Ponting received the most exhilarating working-over since Michael Holding blew away Geoff Boycott in 1981.

A no-ball from Flintoff actually helped England, because it gave him an extra delivery - from which Ponting was dismissed. "They were five of the most vicious deliveries you could ever see," said Gilchrist. "And then Ricky was somehow good enough to get his bat on the last ball to nick it to Geraint Jones. Flintoff stood there like Hercules and his team-mates mobbed him. I remember, in the rooms, watching and thinking, 'We are in big strife.'"

The third day was one for the ages: there were 332 runs, 17 wickets, and approximately four million momentum shifts. It ended with Australia surely beaten: they were 175 for eight after Harmison bowled Michael Clarke with an outrageous slower ball in the final over of the day.

"Jones! Bowden! Kasprowicz the man to go": the last ball of Edgbaston 2005 as Richie Benaud called it © Getty Images

The fourth day was apparently a simple case of England turning up and taking the last two wickets. There was a slight scare when Warne and Lee added 45, but when Warne comically kicked his own stumps down against Flintoff, everyone relaxed again. For about twenty minutes. Then it became apparent that, not only were Lee and Kasprowicz adding runs at speed, they were doing so with alarming comfort. It all happened so fast that, before anyone knew it, Australia needed only 15 to win. That was when Simon Jones, diving forward at third man, dropped a sharp chance offered by Kasprowicz.

The target moved into single figures. By now an entire nation had stopped its day of rest. "Physically sick but still watching," texted the England coach Duncan Fletcher's daughter to her mother. You know sport is truly special when you feel nervous even when you watch replays, and Edgbaston 2005 retains that quality. With four needed, Lee smashed Harmison through the covers; there was a fleeting yelp of triumph from the Australian fans, before they realised Vaughan had a cover sweeper in place and it would only be one run. Two balls later, Kasprowicz fended a short ball from Harmison down the leg side, where the much-maligned wicketkeeper Geraint Jones took an excellent tumbling catch.

England's celebrations were joyously uncoordinated, with players running in different directions before they eventually came together. Harmison broke off from the celebrations to console Lee and then Flintoff did the same, his face a picture of compassion, respect and empathy. The result was one of cricket's iconic photographs, a pictorial code for sportsmanship at its finest.

The cricket world often wonders what Flintoff said, as if he dispensed one of the great pearls of wisdom. The reality was more mundane. "It came out of my mouth, it's nothing profound is it?!" said Flintoff. "It's not gonna be something life-changing!" Lee has a vague recollection. "It was something like, 'Awesome game, bad luck, I thoroughly enjoyed it.'"

Lee cried in the shower area after the game, his batting gloves still on, and then had a beer with Flintoff in the dressing-room. Flintoff sometimes jokes that the sympathetic expression was a smokescreen for an earthy reminder to Lee that England had just made the score 1-1. The reality was far more generous in spirit, of course. Although the essential point of Flintoff's joke is correct: Lee may not be an Aussie bastard, but it was 1-1 rather than 2-0, and the Ashes were ablaze. In no small part thanks to a stray cricket ball.