Gradually, inexorably, the match, the series and the status slipped through England's hands yesterday. Some time today, barring a resplendent and historic batting performance, South Africa will win the fourth Test and the rubber 2-0, becoming the world's top ranked side.
It will be a perfectly just outcome. Hard though England have competed in this final Test, the tourists have been the superior team across all three matches, as they demonstrated again with ruthless application. Hashim Amla gathered another stylish hundred, not quite of the monumental proportions of his triple century at The Oval, but with a similar air of inevitability.
A flurry of wickets in mid-afternoon during a fast, incisive spell by Steve Finn seemed to regenerate England's cause. But South Africa did as they have done throughout, retrenched once more.
They could hardly have timed the end of their innings better. England, needing 346 to win, faced a tricky 13 overs in the evening after a long, hot day in the field. It was all too much for them.
Before the fourth over was out, both openers had gone. Alastair Cook got into a tangle by plunging his front pad forward and across his stumps, and was a cast-iron lbw candidate when the ball swung and thudded into it.
If that was a dismissal caused by suspect method, Andrew Strauss was probably undone as much by events of the past fortnight as by anything else. He might have expected the ball to swing, but in effect he chose to shoulder arms to a straight ball, was on the back foot and hit on the pads bang in front. It was a dreadful and sad way for the England captain to end his participation in the match.
The crowd gave him a consoling round of applause, in fellowship more than anything else, for they had willed him to do well here, given all that he has had to deal with in the Pietersen Affair leading up to this match. It was reported yesterday that the texts Pietersen sent to South African players included instructions on how to remove the England captain. However, the harsh truth is that Strauss has scored 107 runs in his six innings in this series. England needed much more of him. It is not yet time for him to go but it cannot go on like this.
At 16 for 2 the bare statistics of the match seemed academic.
To win the match, level the series and retain their title, England will have to make more runs than they have ever done to win a Test match – they made 332 to beat Australia at Melbourne in 1928-29 – and more than has ever been compiled to win at Lord's – West Indies scored 344 in 1984.
Only the fact that the two highest fourth-innings totals at Lord's have been made this century may give them succour. But they will hardly have gone to bed whistling Dixie.
If England were to stay with their opponents on the fourth day of a wonderful contest, they had to make every opening count.
In essence, that meant creating chances and holding their catches. And in that was distilled their fallibility. Two more catches were spilt, making a total of three in the innings, nine in the series.
These have been tiny but crucial mistakes. South Africa have won almost every key moment in the past month and their batting yesterday again exhibited the fortitude that has marked their whole trip.
There was nothing fancy about their second innings but there were rigour and discipline in abundance.
Having given Amla a life when he had scored only two late on Saturday evening, England added two more errors. A B De Villiers was lured by Graeme Swann into offering a catch to Jimmy Anderson at short midwicket, a sitter as these things go. Anderson hopelessly misjudged it as he tumbled forward.
The least costly missed chance was when Strauss, having become England's most prodigious catcher in Test cricket earlier in the afternoon, put down Jacques Rudolph at slip, also off the suffering Swann. The number of runs added after these misses was 159, the margin between defeat and victory.
Perhaps it has been the incessant intensity of South Africa's cricket that has affected England. At no point have they relaxed or lost sight of their objective.
In many ways, it has matched England's campaign in Australia two winters ago. How long ago that seems now. If only they could have bottled the stuff they discovered then.
There have been clear differences in all aspects of the game. Apart from being aware that they had to miss no opportunities, England also needed a quick breakthrough yesterday if only as a morale-booster.
But they were resisted by the nightwatchman Dale Steyn just long enough to make it frustrating. After he was bounced out at long last, another quick wicket then might have changed the course of the day.
It seemed to have arrived when Swann, with a cunningly flighted, drifting delivery persuaded De Villiers to drive to Anderson, positioned at short midwicket precisely for that purpose. The disbelief was palpable. Something seemed to drain from England.
Amla went on to a serene hundred and it needed a peach of a delivery from Finn which pitched middle and hit off, going up the Lord's slope, to remove him for 121, made from 205 balls. Soon after De Villiers edged to Strauss at first slip, the captain's record 121st catch for England.
When Rudolph, having been spared, edged one going across him, England were back in the hunt.
But South Africa were neither for panicking nor collapsing. JP Duminy and Vernon Philander, as they had in the first innings, put together another half-century partnership. It was simply cussed, determined Test cricket. Get us out if you can, but we're not giving you guys anything for free.
Anderson pitched in with two wickets at the end, Swann got his second thanks to a smart if devious stumping by Matt Prior, who waited for Morne Morkel to take his foot off the ground and then whipped off a bail.
What followed next, however, was chastening.