England’s cricketers will face their biggest challenge on home soil since the 2005 Ashes in the four-Test series against South Africa, which gets under way on Thursday.

Apart from a series defeat to India last year in a heavily weather-affected series, England have not lost at home since Australia toured in 2001.

It is a fine record on paper but one that will be put through the most stringent examination from this summer’s main tourists, with due respect to New Zealand.

Michael Vaughan against Graeme Smith, the Proteas’ devastating triplet of fast bowlers against England’s fragile top seven; Warwickshire’s Ian Bell and Tim Ambrose against the axe and Kevin Pietersen against his country of birth for the first time in Tests are just some of the intriguing battles that will begin at Lord’s and enthral cricket supporters for the next two months.

There is also much at stake for coach Peter Moores. While his predecessor Duncan Fletcher’s reign will be defined as much by the victory against Australia in 2005 as the whitewash he oversaw two years later, the arrival of South Africa signifies the end of Moores’ prolonged honeymoon period.

Successive series wins against New Zealand has done little to silence the growing number of doubters who believe his England side is all talk and living off its reputation while failing to carve out its own identity.

Three series wins in ten hardly suggests a team worthy of its ICC world ranking of third, one position ahead of South Africa, a team with a draw in India under their belts and unbeaten in seven.

The Proteas will run out at Lord’s with the quickest bowling attack to visit here since Shoaib Akhtar, Wasim Akram and Waqar Younis toured in 2001 and the quickest to play in England since the Simon Jones/Andrew Flintoff/Steve Harmison alliance of 2005.

English cricket has delivered nothing noteworthy since then. While much of the personnel has changed since 2005, not much has changed recently.

Tomorrow, for the first time ever, a sixth successive unchanged England Test side will take the field.

‘Stability’ is the selectors’ buzz word – but a South Africa side rich in runs, wickets and full of expectation is a different proposition than a meek New Zealand side just happy to be here.

The case for Stuart Broad and the mercurial James Anderson as front line, wicket-taking bowlers will be scrutinised more than ever with Flintoff, Harmison, Matthew Hoggard, Chris Tremlett, Simon Jones and Sajid Mahmood hastily finding form in county cricket.

But more questions will be asked of England’s top order, and especially of Tim Ambrose’s faltering challenge to be seen as the long-term answer to the country’s wicketkeeping worries.

The selectors may argue that England’s top six boast career averages over 40 but, in their past ten Test innings against New Zealand, only Strauss (54) and Pietersen (44.50) have bettered that.

A top seven comprising Alistair Cook (30.8), Vaughan (32.3), Bell (36.87) Paul Collingwood (30.66) and Ambrose (30.44, in nine innings) suggests fragility.

In contrast, all but one of South Africa’s top seven – wicketkeeper Mark Boucher – average above 40 in the past 18 months.

Cumulatively in 2008, England’s top seven have scored 2,462 runs in 69 innings compared with South Africa’s 3,438 in 73.

Smith (810 runs at 73.76), McKenzie (621 at 77.62) and AB de Villiers (498 at 62.25) have been in particularly fine fettle.

But worryingly for England, batting is no longer seen as South Africa’s strength. All three of their main strike bowlers have been recorded at over the 90mph mark consistently in the past 12 months.

Dale Steyn, with a 97mph delivery, tops that list in speed terms but has turned three years of steady improvement since his arrival in Test cricket in 2004 – when he made his debut against England – into a meteoric rise.

The former Warwickshire opener passed Allan Donald’s record as the quickest South African bowler to pass 100 Test wickets, perhaps unsurprisingly seeing as he has taken 78 wickets since the start of 2007.

Steyn, rated second behind Muttiah Muralitharan in the world rankings, is well-supported by Makhaya Ntini, currently lying fifth, and Morne Morkel, who has been tipped by Charl Langeveldt, the former South Africa seamer, as his side’s “danger man” this summer.

The 33-year-old retired from international cricket in March after he was selected for South Africa’s Test tour of India at the expense of his white compatriot, Andre Nel, who boasted a far superior record.

However, Langeveldt’s refusal to be used as a pawn in Cricket South Africa’s controversial game of “transformation” – a quota system that, for example, sets a target of seven non-white cricketers in any Proteas squad of 15 or more – could be seen as reflection of the current mood in South Africa cricket, which is as free from political interference as it has been since re-instatement.

That alone could provide the biggest boost to the tourists’ chances of victory this summer.

Langeveldt believes Morkel, a genuine fast bowler capable of producing inhibitive bounce from his 6ft 5in frame, will be the biggest threat, particularly to Pietersen and Bell, the two batsmen he says Smith’s side will be most focused on dismissing cheaply.

“Dale Steyn has been very good for a long time,” said Langeveldt. “He has played a fair amount of county cricket [he took the most wickets taken in limited overs cricket for Warwickshire] so he knows the conditions here and he’s capable of swinging the ball at 150 kph.

“He will be able to bowl on wickets here even if they are flat. But there is a good balance in the attack. I think Morkel will be the one to watch and, alongside him and Steyn, they have Ntini.

“He is just a workhorse and will toil away for his team, which will allow South Africa to a play a spinner [who will be another former Warwickshire bowler, Paul Harris].”

Given the close relationship Langeveldt retains with the Proteas’ dressing room, he said he was expecting a call from the players keen to tap into his wealth of knowledge of bowling in English conditions.

Of particular interest to Morkel would be the battle Langeveldt won against Bell during Warwickshire’s county championship match at Derbyshire in May.

During his brief international career the aggressive 25-year-old has developed a habit of targeting big names in opposing batting line-ups and, although he has hitherto been cagey about the player he fancies in England’s side, Langeveldt believes the Warwickshire batsman will be his top priority.

In India, for example, Morkel set his sights on Rahul Dravid before giving one of the classiest batsmen of his generation a torrid time on benign pitches. He dismissed Dravid, caught behind, twice.

Langeveldt said: “Bell’s trigger movement is back and across so staying at him with a good shape on the ball will be very important. That is why I think Morkel is going to be the one to trouble Bell.

“And I think Morne knows that, too. Bell is looking in good nick. He has good foot movement so I think he will have a good end to the summer.

“I was trying to bowl at his fifth stump because of that trigger movement and I think that is what the South Africans will do. They will try and get him out by nicking off and using the short ball to push him back in his crease.”

The Bell/Morkel confrontation will not be the only one to look out for.

Relations between the two captains are not good and then, of course, there is the Pietersen factor to throw into the cocktail, which will take the bitterness level beyond Mojito to Molotov.

Both sides know the role Pietersen plays will go a long way to deciding the series. Langeveldt added: “Kevin and Graeme Smith do not get on – but the other guys in the SA team don’t have a problem with him.

“When he started playing in South Africa he was batting at seven or eight and bowling off spin.

“It is much harder to score runs there because of the quality of the club cricket and I take my hat off to him for the decision he has made, and the way he has made it work for him.

“But people back home are surprised at how well he has done, that’s for sure. We haven’t played against him in a Test series before but we know he is going to be aggressive.

“However, as bowlers in South Africa we tend to be aggressive. A lot depends on the wickets we play on. Again Morkel could be the main threat to KP because of the bounce he gets.

“If they stay injury free, both of them will be the danger men.”