England have led in the Ashes before and lost. It remains perfectly possible for them to be deprived of the great prize at The Oval next month and all the noises from the camp after the historic victory at Lord's on Monday unite as one voice: "We ain't won nothin' yet."
The task of clinging on to, or increasing, the lead is made much tougher by the enforced absence of Kevin Pietersen, whose run of 54 Test matches since he made his auspicious debut in 2005 is over. There is a certain poignancy in the fact that his sequence began at Lord's against Australia and ended at Lord's against Australia.
England must do without him for the first time since he was selected and the reluctance to be bullish is understandable. They will spend much of the next three days hoping that they do not have to do without their Lord's champion, Andrew Flintoff, who is bowling as he has never bowled before.
Flintoff will do anything he can to ensure he is fit for the match despite the protestations of his right knee. He was still in discomfort two days after his heroics at Lord's which brought him deserved second-innings figures of 5 for 92, but he remains convinced that rest and rehabilitation will do the trick before Thursday.
This may be so because Flintoff is both courageous and cussed, but England could still have an additional problem for the following Test match in Leeds. This begins only three days after the Birmingham game finishes and if Flintoff's knee is in a similar state as it was when he finished at Lord's he will not be able to play.
Had the Birmingham match followed three days after the Lord's match, for instance, he could not have played – not without a pair of crutches anyway, which, come to think of it, is not beyond him. In 1997, England took a 1-0 lead and spent the rest of the series being humiliated. In 1936-37 in Australia it was possibly worse. The team led by Gubby Allen went ahead 2-0, Don Bradman twice being dismissed for a duck. In the third match, Bradman reversed his team's batting order on a sticky wicket, went in at 97 for 5 when it had eased and was ninth out for 270. He led the team to victory by 365 runs, scored hundreds in the next two Tests and that was that.
But England, while being cautious, would do well to remember that this Australia is not the Australia either of 1937 (it has no Bradman for a start) or of 1997 (it has no Glenn McGrath, no Shane Warne, no Steve Waugh, though it does have Ricky Ponting, the best Australian batsman since Bradman).
The sides are close, and how close can perhaps be measured by the fact that Australia were so dominant at Cardiff but England were equally on top at Lord's. However, Australia have plenty of problems, with both their new stars, the batsman Phillip Hughes and the fast bowler Mitchell Johnson, out of form.
There will be no extravagant changes to either side for the much awaited Third Test which begins at Edgbaston on Thursday. England will bring in Ian Bell for Pietersen but will not name any additional batting cover. Should a batsman break a finger in the Edgbaston nets, they say they know who to call on. It ought to be Rob Key because he has Test experience but there is a growing feeling that the cause of the South African Jonathan Trott is being promoted by Ashley Giles, one of the selectors and his coach at Warwickshire. Trott has plenty of form, with three Championship centuries and an average above 100.
England are being urged to ask Bell to bat at No 3 because Ravi Bopara has looked so fragile there so far. Given the natures of both Andrew Strauss and coach Andy Flower, and the faith they have invested in Bopara, they will probably resist the call. It would be deemed to be unfair on both batsmen.
Bell was dropped from the No 3 position, and from the team, after a poor series of series which culminated in an ill-advised and badly executed cut shot on the stroke of lunch in Kingston last February. Shortly afterwards, England had been bowled out for 51 and Bell's Test career was put on temporary hold.
He had expected to play no part in this Ashes and has been giving much thought to his approach to cricket and to the demands of the international game. He would bat at No 3 if asked, as he has filled every position in the order including opener in times of emergency, but it would be overburdening him.
Bopara, however, has looked out of his depth so far and to watch the struggle that he and Kevin Pietersen had on Saturday afternoon at Lord's was to understand what being out of form means. Naturally of sunny disposition and sure of his talent, Bopara must be starting to wonder if he really is as good as some judges have maintained.
He has forgotten that Test innings need pacing and they need rhythm. He has lacked both those elements in the opening two matches of the series and in the next three Australia are going to let him know what they think of him, and keep letting him know.
After it, he will either have come through as a more complete player, a genuine Test batsman, or he may face up to the grim prospect of rebuilding his entire career. Flower's careful, studious public pronouncements indicate he still thinks highly of Bopara and is not about to have his judgement swayed by a couple of failures. It is as if he suspected what might happen.
Without Pietersen the order assumes a brittle look but that would be true of any side around. His absence could be either the making or the unmaking of Bell as an authentic batting champion. Bell has a meek demeanour but when he says he wants to play 100 Test matches for England he is not joking. He will need a few breaks on the way and occasionally he might have to pretend that he is Kevin Pietersen, but this could at last be Bell's time.
It may not help him, as it should have done, that the match is being played on the ground he knows better than anywhere else. The poor weather of the past fortnight means the pitch for the match is likely to be underprepared. The groundsman Steve Rouse, who is given to slight pessimism in predicting how his pitches might play, said the surface is like jelly at present.
Considering how the sides bowled at Lord's, a low-scoring match on a dodgy pitch might be to England's liking. Graeme Swann was almost as impressive as Flintoff at Lord's and Jimmy Anderson's moments are no longer few and far between.
The selectors may be tempted to recall Steve Harmison, who according to one report yesterday is to retire from international cricket at the end of the series, presumably because he will miss his pal Flintoff. But equally they will be loath to jettison Graham Onions despite a seeming tendency to tire and lose his length as innings wear on. Monty Panesar, batting hero of Cardiff, will be in the squad and although England still like the idea of having two spinners, it worked out so catastrophically for them in Cardiff that a resumption so soon is improbable and risky.
Australia will resist making changes. Hughes will stay for at least one more match and Ponting's entire strategy is probably based on Johnson coming good soon. He had better start now. Otherwise, England could be 2-0 up and have glory in their grasp.
England had been soundly beaten in the First Test at Lord's and the Ashes campaign looked as if it would go the way of all others in the previous 15 years. But then Glenn McGrath stepped on a ball in the outfield during practice and was ruled out. Michael Vaughan lost the toss and was inserted by Ricky Ponting.
However, Marcus Trescothick (90) and Andrew Strauss (48) put on 112 in just 25 overs and Kevin Pietersen (71) and Andrew Flintoff, with 68 off 62 balls including five sixes, added a further 103 for the fifth wicket as a total of 407 was posted. Australia managed 308 in reply but England slipped to 182 all out in the second innings, only Flintoff (73) providing any resistance as Brett Lee (4 for 82) blasted England's top order and Shane Warne (6 for 46) mopped up the rest. That left Australia a gettable target of 282 to win. At 175 for 8 and Michael Clarke gone, the game looked to be up. But Warne and Lee added 45 before the former bizarrely trod on his stumps: 62 to win, one wicket left. Michael Kasprowicz proved just as hard to dislodge. The visitors edged closer and closer, until just three runs were needed.
But Steve Harmison managed to get the ball to rear up past Kasprowicz's shoulder and it touched his glove. Geraint Jones flung himself forward to catch the looping ball and Kasprowicz was given out by Billy Bowden – even though it transpired that he had taken his hand off the bat and thus should not have been dismissed. Flintoff's consoling of Lee, the not out batsman, became an iconic image of sportsmanship.