Stewart's absence, after just one home Test in charge would be a huge blow to England's morale. As captain and wicket-keeping all-rounder, he is nigh on irreplaceable, and the selection panel have sent for Graeme Hick and Jack Russell, to cover for two of his roles. A third, Nasser Hussain, will assume the captaincy, while Steve James is on standby to replace Butcher, should the opener fail a fitness test this morning.
Hussain's only experience of captaining England is a one-day international in Auckland two winter's ago, a match England won. "I know I'll have to stay thinking for the next five days," said Hussain, knowing that even if Stewart starts, the slightest recurrence of the trouble would require him to take charge.
The England captain has suffered from similar problems before - he says the problem afflicts him once or twice a year. In fact, it was a back spasm that prevented him from keeping wicket for two sessions in the Lord's Test match last year. On that occasion, John Crawley kept wicket until the spasm had subsided, something both his team-mates and England supporters hope will have happened again by the time he gets to the ground this morning.
"I felt it when I woke up yesterday," said Stewart, who will have no doubt have been popping anti-inflammatory tablets for the last 24 hours. "On past evidence, it's usually OK after 24 hours and I'm reasonably hopeful."
Instead of resting, however, he spent 30 minutes keeping wicket to Robert Croft and Mark Ramprakash under the supervision of Alan Knott, a move that suggests it is nowhere near as disabling as the back spasm Graham Thorpe suffered during the one-dayers.
According to the chairman of selectors, David Graveney, there will be no halfway house whereby Stewart will rule himself fit to bat but not to keep wicket. As someone with the best current batting record at Lord's - in 10 Tests he has scored 961 runs at an average of 53.38 - it seems a curious decision, particularly as his absence will have to be filled by two players anyway, presumably at the expense of a bowler.
Despite his absence from England colours for 19 Tests, Hick, with 887 runs at an average of 68, is one of the season's form horses. A recent entrant to the 100 hundreds club, Hick has made five three figure scores this season, although one was against Oxford University.
Form is also the reason that the 30-year-old James, with 733 runs at 66.63 for Glamorgan, gave him the edge over his close rival Darren Maddy. Picked for the one-day squad earlier in the season, Maddy's poor form in the Championship, following a brilliant England A tour last winter, has probably cost him his chance.
Judging by yesterday's gloomy progress report on Butcher, James, having come close last season, seems almost certain to make his Test debut. If he does, he will walk to the crease with his old Cambridge University captain, Michael Atherton.
Firm friends for the last decade, Atherton apparently rings James whenever the Glamorgan player gets a hundred. But before the public at large begin to think there is a soft, gooey side to Atherton, the nature of the call always begins with the inquiry: "Did they have a third man?" - a matey dig at James' penchant for scoring the bulk of his runs behind square on the off side.
"I'm obviously delighted, though I wish Mark Butcher all the best," said James, who became aware of his call-up while in the gym at Cardiff, waiting for yesterday's rain to relent. "When Mike Fatkin [Glamorgan's cricket secretary] and Matthew Maynard came over looking serious, I thought I was in trouble, instead of being asked to cover at Lord's."
Whoever plays, it would be cruel fortune if England are denied the services of both their captain and their left-handed opener, the latter so effective in disrupting both Allan Donald's and Shaun Pollock's line in the First Test.
On a pitch still retaining a good deal of moisture, England could probably do without blooding a new opener, although South Africa look set to take the plunge, replacing the lunging Gerhardus Liebenberg with Adam Bacher, the nephew of Ali Bacher, the managing director of the South African Cricket Board.
With pitches at Lord's having a tendency towards uneven bounce, England will probably want to bat first, though any rain or overcast conditions this morning will probably persuade the successful caller to bowl.
If it does, England in spite of all their injury problems surrounding their captain, will also have to decide which of their pace bowlers to leave out, though Croft could miss out if rain, forecast for most of today, causes the start to be delayed by more than a few hours.
ENGLAND SQUAD (For second Test, v South Africa at Lord's today): M A Atherton (Lancashire); M A Butcher (Surrey); N Hussain (Essex); A J Stewart (Surrey, wkt, capt); G P Thorpe (Surrey); M R Ramprakash (Middlesex); M A Ealham (Kent); D G Cork (Derbyshire); R D B Croft (Glamorgan); D W Headley (Kent); A R C Fraser (Middlesex); C E W Silverwood (Yorkshire); S P James (Galmorgan); R C Russell (Gloucestershire, wkt); G A Hick (Worcestershire).