South Africa's depth comes to the rescue

Nothing more than a glance at the score will reveal that South Africa had their worst day with the bat in the series so far. What it will not expose is why their line-up fared poorly on the liveliest surface of the series against an attack that showed more intent than it has done in the two matches they have played so far.

With the major consideration about the conditions being the quality of the outfield, the pitch was almost forgotten in the build-up. Both captains simply expected a "good wicket," as they always get at Lord's. And this one was good. It had enough in it for the toss to be a one Andrew Strauss told his dressing room he would rather have lost, because he was not sure if the overhead clouds would hold to justify bowling first or if they would clear, as they did in parts, and batting would be the better option.

One journalist said it had the most grass he had ever seen on a Lord's pitch, in 12 years of covering matches there. Although not green enough to be called green, there was a definite tinge to it and with the clouds rolling in for the morning session and humidity high, it ended up being a bowler's morning.

Later in the day, the sun came out and batting was easier but the uncertainty of when they would return and how much was in the surface compared to the sky seemed to have had an effect on South Africa. "There is more in this wicket than the other two," JP Duminy said. "There was definitely more carry than Headingley and The Oval."

There was also more in the England tank. All the seamers seemed a touch quicker, Stuart Broad most noticeably. James Anderson bowled one of his best spells of the series, getting considerable movement and Finn was a different man to the one who continually smacked the non-striker's stumps at Leeds. There was assistance for Graeme Swann as well, and as a unit, they operated with more purpose.

The field placing was better thought out, with a leg gully to Graeme Smith and a short leg in for a lot of the day. More importantly, the attack clearly made an effort to work to strategies, which they had not done with as much conviction previously. As a result, they were rewarded but there was a third element that contributed to South Africa's showing as well: their own lack of application.

Two of them, Smith and Duminy, were dismissed chasing wide balls that they did not have to play at. Duminy's was a particularly poor shot, probably the worst of the day, which came after he had formed a 72-run sixth wicket stand with Vernon Philander.

Instead of continuing to usher the tail through to the close, Duminy succumbed to the third delivery bowled with the new ball. He was guilty of both lack of footwork and lack of thought and threw away a start that could have developed into a Melbourne-esque innings, perhaps not of the same magnitude as the century he made at the MCG in 2008, but of the same fight.

He shrugged it off in a manner too casual to convey that he understood the importance of batting on. "It was a poor shot but I was happy with the innings until then," Duminy said. "I take full responsibility for it, it wasn't a lack of concentration, it was just a poor shot." Everyone plays poor shots, of course, but to play one when four of your line-up before you have done the same, hints at irresponsibility, a trait Duminy has managed to rid himself of but it returned today.

Alviro Petersen and Jacques Kallis were both caught down the leg-side, although there is debate surrounding whether Kallis was really out. Both of them may be considered unlucky but both put themselves in positions where luck would not have become a factor by not selecting the shots they played. Petersen seemed not to want to offer a stroke to a delivery angled down leg but ended up half-heartedly doing so and did not get his hand away in time.

Kallis had an uncomfortable start against the short ball and then also erred when faced with the leg-stump line. Steven Finn recognised that both chances could have gone "six inches" further and resulted in four runs which makes the margin for error small enough for South Africa to have wanted to avoid rather than tempt.

Jacques Rudolph partnered Duminy in rescuing South Africa and showed patience for someone who has not had much time in the middle and may not be expected to have. He played Graeme Swann well until he played across one and inside-edged onto middle stump. Rudolph's inability to convert starts, especially when he most needs to, may stand as one of the concerns for South Africa after the tour. His half-century batting as an opener in the second innings at Headingley is an exception to some extent, because the situation did not call for as determined effort as the collapse of today did.

Only Hashim Amla was the victim of a delivery that deserved a wicket. Finn got the ball to nip back into him and his lack of footwork against a challenging ball caused his downfall. AB de Villiers also cannot be held entirely to blame for being induced into the drive by Anderson, who bowled well for most of the day.

What a day like today illustrates to South Africa is that it was not for the additional batsmen at No.7, they would have been in a far more serious situation. Duminy slotted into that role and used the opportunity to show why he was put there but South Africa are still in a squeaky bum position. Unlike in the other matches, they have not got away from England, as Finn pointed out and they have been made to work for what they have. Duminy said they "would like to get to 300" and if they don't get much further, England will have made a proper fist of a must-win match.