Another thrilling day of Twenty20 cricket delivered the biggest shock so far as Zimbabwe beat the Australians by five wickets in Cape Town, South Africa.

Zimbabwe needed 12 to win from the final over, bowled by Nathan Bracken. It seemed a big ask, but their prospects improved when the first ball was skilfully deflected for four by their opener Brendan Taylor, who played a nerveless hand throughout. Taylor then repeated the feat on the penultimate ball and Zimbabwe were home.

Beset by political troubles, Zimbabwe have suspended themselves voluntarily from Test cricket indefinitely. There are many within the sport who believe they should not be allowed to compete at all until the tyrant Robert Mugabe is deposed. But whatever the real-world backdrop, this team have clearly prepared themselves with great efficiency for this tournament. Their bowling was disciplined, and their batting cool-headed. England will have to be on their game today to prevent a similar disaster.

Australia made a shocking start to the game, lurching to 19 for three in the fourth over, and never fully recovered. Perhaps their batsmen were lulled by the dynamic tone set by South Africa's win over West Indies, and thought it would be easy to score at 11 an over. But the Wanderers ground is 1,000 miles further north and 1,750 metres higher up than Cape Town, which has suffered heavy rainfall in recent months. Yesterday's pitch was slow and two-paced, and the big shots attempted by Australia's top three all backfired.

Andrew Symonds and Mike Hussey began the rebuilding process, but when they both stumbled out of their creases, the innings stalled again. Brad Hodge, the world's leading Twenty20 run-scorer, played some commanding shots in an unbeaten 33, but the tailenders could have given him more strike and Australia's total of 138 for nine always looked vulnerable.

This was never going to be the sort of pitch that Brett Lee enjoys, and the Zimbabwean openers gleefully snicked and carved his first two overs for 19 runs. Vusi Sibanda played some crunching cover drives, before the introduction of the steady Stuart Clark began to drag the Australians back into the match.

After a brief rain-break, the teams ran neck and neck until that dramatic final over. When the final boundary eluded Clark's grasp, the whole Zimbabean squad charged on to the field, lifting Taylor into the air and performing a lap of honour for a delighted crowd. The intense sporting rivalry between Australia and South Africa meant that this result went down particularly well.

Could Twenty20 cricket be Australia's Achilles heel? World champions, Ashes-winners, holders of the Champions Trophy, the Australians have dominated every form of the game for the past two years. Then came this upstart format, which they have treated with lofty disdain. A couple of warm-up games proved insufficient preparation as the tournament favourites were unseated.

As Australia captain Ricky Ponting admitted afterwards: ''Our batting has been diabolical. We need to show this game more respect.'' Telegraph.uk