England's performance showcased the spirit in Andrew Strauss' side
England's superb six-run win against South Africa is a real testimony to the character of Andrew Strauss' side.
Having shown enormous spirit and temperament to win the Ashes this winter, they have been a bit flaky for the first three games of the World Cup.
But they showed a lot of character in the field and with the ball to win the game in Chennai.
It was the kind of performance we expect to see of this England side at the World Cup and will remind the players of the way they played in the recent Test series in Australia and how good a side they are.
At one stage during Sunday's game, it was looking as though it they failed to beat Bangladesh in Chittagong they would not make the quarter-finals, so there will be massive relief at this result, which should now get them through.
They have a long journey on Monday, but they will feel much happier about it than they would have been had they lost here and needed to win on Friday to stay in the tournament.
Importantly, the bowling was much better than in previous matches, albeit in conditions that were much more helpful.
In truth, the pitch did too much. I am all for surfaces that suit bowlers to an extent because you want them to win the game but this was too far the other way.
Pietersen scored just two runs in Sunday's victory
England's bowlers still had to bowl well - straight and on a length - and they did. They got lbws, they hit the stumps and spinner Graeme Swann looked like he could take a wicket with every ball.
But the bowlers really had to put their backs into it and make up for what was a poor batting performance, that left England 40 runs short of a good total.
They couldn't have got off to a much worst start - losing two wickets in the first over to leave them 3-2.
Opener Kevin Pietersen failed and was again out to a left-arm spinner. He keeps saying he does not have a problem, but they keep getting him out and he now averages 23 in 27 matches since scoring his last century. If people were not talking about it already, now they certainly will be.
However I doubt England will make any changes - they are committed to having him open - but they can look back to the time he has got starts and got himself out and will feel it is time for him to knuckle down a bit and get some bigger scores.
However, when you are 15-3 in the third over, clearly you are unlikely to go on and post a big score and winning the game from this position was a very good achievement indeed.
The defeat will lead to familiar taunts aimed at South Africa; suggesting that when the pressure is on, they can not hack it. This is something that will no go away until they start winning games like this.
I still think they have the personnel to win the World Cup, and Imran Tahir's leg spin (he took 4-38) gives them an edge on these pitches, but have they got the bottle?
The most important lesson England can take away from Sunday's match is that they must, on surfaces that they do not know very well, take longer and be more careful about assessing what is a good score when they are batting first.
I suspect it will be a very low, slow pitch in Chittagong, so it will have done England no harm to have played a game on such a pitch in Chennai.
They return here as well for the West Indies, so they may well be on a similar surface until they qualify, which, after Sunday, looks a lot more likely.
Jonathan Agnew was speaking to Phil Dawkes. Join Jonathan and Geoffrey Boycott for the