Ahead of their derby clash with Ireland in Guyana, England may be feeling slightly nervy.

Previous World Twenty20s have been marked by memorable shocks. Last year began with the Netherlands' victory over the hosts. Smaller upsets followed when Ireland knocked out Bangladesh and Australia failed to progress beyond the first round.

In 2007 there were other tales of the unexpected. The triple world champions were cowed magnificently and hilariously by Zimbabwe while the West Indies fell at the first fence against Bangladesh. All this so soon after India and Pakistan had left the ninth World Cup at the earliest stage.

The current event is due a giant-killing and from the remaining four fixtures it is the Tuesday evening game that stands out. New Zealand will surely be too steady for Zimbabwe, Afghanistan are there for the ride and Bangladesh missed their chance against Pakistan. Despite playing well in Duckworth-Lewis defeat against the hosts, the weakest big-eight nation will have to be careful against strong associate challengers.

Paul Collingwood's men delivered perhaps their most impressive batting display in the format against the West Indies on Monday. But three years ago at the Wanderers Chris Gayle hit a century as his team broke the world record innings total - and within two days the Tigers had put them out of the tournament. Form is no guide in twenty20, such as it exists at all.

Ireland will tell themselves that almost anyone can beat anyone in twenty20 and certainly anyone can beat England after their Dutch disaster. William Porterfield knows first hand how vulnerable they can be - no-one at Stormont when the two teams met last August has yet worked out how England emerged as victors.

At the same time Ireland are lacking the conviction that has seen them established as a recurring success story in recent international tournaments. On Friday night teenager George Dockrell bowled them into position to attack the Windies only for naïve captaincy and loose bowling to let the hosts off the hook. The indifference in reply, losing three quick wickets with rabbit-in-the-headlights batting, reinforces the view of a team unsure of themselves on the big stage.

The world game needs new blood and Ireland are streets ahead of other associate nations. If they are to stumble this is an unfortunate time. It isn't easy, though, when your best players decamp to the neighbours at the first sign of form. Eoin Morgan has been friendly and respectful to his countrymen this weekend. But his focus and ambition point to a simple fact: the best Irish players don't see their future with their own country.

This lack of domestic enthusiasm is replicated among the public. In a sport-centric nation Tuesday morning's water-cooler talk will review the weekend's Heineken Cup rugby, Premiership football and league hurling. Mentions of Porterfield will be minimal. Irish cricket fans even tend to support England when they have no involvement themselves - treasonous behaviour in mainstream events.

For much of the last three years England would have been quite right to enter such a must-win, no-win encounter with trepidation. But the momentum is with them and against Ireland - a trend personified by Morgan, electrifying once again on Monday. We have been accustomed to surprises in World T20 competition but the 2010 instalment looks almost certain to return all eight favourites to the second round for the first time.

Peter May