England's epic winter officially begins today only nine days after the end of their interminable summer. The main concern for Nasser Hussain's team must be that the darkest day will arrive early and hang around until next spring.

Win against Zimbabwe in the opening match of the Champions Trophy and the sense of relief will be out of proportion to what it means: a chance, but still no more, of progress to the next round, the semi-finals.

Suddenly, the match is no longer the formality it once appeared to be. Pool Two has become that familiar, unmissable part of sporting festivals. It is the "Group of Death".

For England it is merely the first stage on their journey which will be followed in rapid succession by the Ashes, the VB triangular competition and the World Cup. Every other team in the world is facing a similarly intimidating schedule but not all of them have seen the seasons squeezed quite so close. India are an exception to that but they go on longer world tours than the Rolling Stones.

Two months ago, perhaps two weeks ago, England would have been clear favourites to beat Zimbabwe and make the second pool match against India on Sunday a straight knock-out. But injury, fatigue and the sense that they mislaid their form have all arrived at once.

Hussain is not quite the leader now that he was in the middle of the summer. Tiredness does that.

There will be at least five changes in the team which plays at Premadasa Stadium today from the one which lost the NatWest Series final at Lord's a little more than nine weeks ago. It makes them distinctly vulnerable.

The apparently comforting statistic that England have beaten Zimbabwe in eight consecutive matches should be ignored. Zimbabwe might have more significant troubles of their own – a country racked by political unrest – but they showed how capable they were of rising above them in their desperately close encounter against India last Saturday. If their slow-medium bowlers get it straight they might suit the Premadasa pitch.

"They have played together a long time as a unit," said England's coach, Duncan Fletcher, who was one of Zimbabwe's most successful captains before they gained Test status. "They were magnificent against India and were in it right until the end. This is one of the most inexperienced sides England have taken on to the field."

Heath Streak, Zimbabwe's captain, said: "England are missing a few key players. If we play well we can win." What he meant was that if Andy Flower plays well England will know they are in a game. Flower made a wonderfully gritty century against India, his best score, and this great cricketer lifts the whole team.

England will almost certainly award an international cap (a very fetching blue and light baseball affair in synthetic materials with the logo of the team sponsors emblazoned on its front) to Ian Blackwell. After his 56 and 3 for 17 in the warm-up against Bangladesh the Somerset left-hander would be entitled to ask what more he had to do if he was left out.

He will be allowed to play his own game, which might mean a plethora of big, clean hitting if he chooses wisely. There is a bucolic air about Blackwell and the way he hits the cricket ball has the joyful air of the village green about it. He is several pounds heavier than you expect of the professional cricketer in the 21st century but that will not harm his standing with the fans.

"It can be difficult to bat at No 7 or 8 when you first come into one-day cricket, far more difficult even than opening in a Test," said Fletcher. "You're trying to establish yourself and get a few runs on the board. After a while it's quite a nice position because you're free but it's hard at first. Blackwell has shown himself already as a willing learner."

He may need to be an extremely quick one, too. Otherwise, the nights will draw in.

ENGLAND (from): N Hussain (Essex, capt), M E Trescothick (Somerset), N V Knight (Warwickshire), R C Irani (Essex), A J Stewart (Surrey, wkt), I D Blackwell (Somerset), J N Snape (Gloucestershire), D G Cork (Derbyshire), A F Giles (Warwickshire), A R Caddick (Somerset), M J Hoggard (Yorkshire), R J Kirtley (Sussex).

ZIMBABWE (from): H H Streak (capt), A D R Campbell, D D Ebrahim, A Flower (wkt), G W Flower, S V Carlisle, G J Whittall, D A Marillier, S M Ervine, R W Price, D T Hondo, T Friend.

Umpires: R Koertzen (SA) and S Bucknor (WI).