In one hour at Trent Bridge on Thursday morning, the world changed. Or, if that is an exaggeration, the world of cricket in which we all revolve shifted on its axis a little. It was midday when Ashton Agar came to crease, his team reeling from a scoreboard that read 117 for 9. The witches who had stirred their pot to predict 10-0 in the coming months looked on with sadistic anticipation.

By 1pm, the pre-written storyboards were in the bin. There was a new tale to tell: the tale of a 19-year-old Australian, born in Melbourne to a Sinhalese mother, slaying Goliath. Unheard of, unseen and unbelievable - Ashton took us to Disneyland.

Because Australia were nine wickets down, lunch was delayed by half an hour - a new wheeze from the ICC that took us all by surprise - and so the fantasy continued: dazzling cuts, pulls and drives that smashed record after record along the way. From that point on the match, and the series, was alive.

Australia needed something, or someone, like this. Not just the blokes here at Trent Bridge but the blokes and the Sheilas back home. It is a proud land and requires its sporting heroes to front up. That Agar looked good was okay, that he played good was magic.

Inspired, the Channel Nine viewing figures have gone through the roof and the network are comfortable that their cricket gamble will pay off. Kerry Packer's erstwhile channel spent handsomely for the rights a month or so back. Had Brad Haddin and James Pattinson managed 15 more runs on Sunday, the celebrations at Nine HQ would have matched those at Cricket Australia, where the rehab of the team is on everyone's lips.

The fact is that Australia loves and cares about cricket. The folk at the Nottingham hotel told stories of friends and family sitting up through the night and of expats glued to their 50-inch screens in Hong Kong, Kuala Lumpur and the like. They said that Nine was cricket's home in Oz and that Michael Clarke was winning friends that he never thought he would have.

Clarke gave a marvellous interview at the post-match presentation, as did Alastair Cook - both men relieved but for very different reasons. Cook directed a team that conceded 228 runs in the match to the Australian tenth wicket. That is bad karma. Had it led to defeat, the nights ahead would have been long. Clarke saw his team go to the wire without a significant contribution of his own. And he saw Agar put out a marker. There you go boys, he might be saying, a kid from the west got under England's skin. It is not just me, it is him, and it is also you who can resist them. Play the ball, not the man, and enjoy it for what it is, an upscale game of cricket.

Having said that, it was an especially hard match: a match that needed patience and clear thinking. The umpiring and decision review moments threatened to overwhelm the cricket itself but, though the DRS had the final say, the tension and thrills created by the players won through.

It is too simplistic to say that the DRS should be taken out of the hands of the players and left to the umpires. The principle is strong enough but the reality is that no on-field umpire will risk a decision without referring it to his mate indoors, who has the considerable advantage of television replays at his fingertips. Why would he?

Even in defeat, the Australians are in a better place than they could have dared hope at midday on Thursday

Morality, what remains of it, would be replaced by technology as the minutiae of the game. Every decision will go upstairs; it will have to. And when it does, the technology will be proved almost as fallible as the umpire. Ask Jonathan Trott. What's more, all decisions will take forever and the game's natural rhythm will be lost.

The DRS is not a mile away from fulfilling its responsibility. Maybe the teams should be allowed one option rather than two, and that way they can pretty much forget about it until they know they have been wronged.

To satisfy the moments that are obvious enough after the event, allow the third umpire to intervene when it is immediately clear to him that a serious mistake has been made. In other words, give both player and third umpire a piece of the pie but leave the fellows on the field to do their job up until the point of extreme misjudgement.

Finally on this subject, the ICC must take responsibility for decision-making technology. The broadcaster is providing for its audience not for the administration of the game. Over these past five days we have been reminded just how emotionally charged cricket has become, particularly in Ashes cricket, and we would see it too if India were to play Pakistan.

The crowd is wound up by the daily anthems and, mostly, the players wear their hearts for all to see. They are under the glare of a demanding audience in a game needing to hold its place in a changing world order. The ICC can help by ensuring that the manageable controversies are kept to a minimum.

For all that, and even in defeat, the Australians are in a better place than they could have dared hope at midday on Thursday. Though Clarke would not have it, they are also in a better place than before the series began. They have seen that England are vulnerable and that the theatre of the Ashes is as challenging for old hands as for new.

The brilliant selection of Agar should now be matched by a volte face on David Warner. If he is at Heathrow, heading for an Australia A game in Zimbabwe, send a taxi to bring him back. Warner has talent - with bat, ball and in the field - and attitude. Channel that attitude to the cricket at Lord's; it is a stage that might make him. There is no time for Australia to waste.

Mark Nicholas, the former Hampshire captain, presents the cricket on Channel 9 in Australia and Channel 5 in the UK