England's losing Twenty20 run is a major concern to Ashley Giles for a world tournament in which he admits they will be underdogs.

Giles' team have lost their last five matches and two series in the shortest format, 3-0 away to Australia and 2-0 with one still to play at the Kensington Oval against West Indies.

England's limited-overs coach therefore faces an unenviable challenge, win or lose in Thursday's final match here, to try to refine the skills and maintain confidence for the imminent mission improbable at the ICC World Twenty20 in Bangladesh.

There, over the next three weeks, England will be tested by the world's best in conditions sure to highlight many of the collective shortcomings so evident and worrying in recent times.

Giles shies away neither from results, underlying causes or short-term implications which may yet put his hopes of becoming England's next head coach in jeopardy.

"We've lost five in a row," he said.

"Clearly we're not playing very good Twenty20 cricket, and we haven't done for a period now.

"We'll go into that tournament as underdogs anyway.

"Every game we play, we go and play to win. But we're just not getting into matches. That's the biggest concern.

"Four of the last five occasions, we've been three down at six overs.

"If you consistently do that, you're behind the eight ball."

England repeated that unhelpful habit as the Windies clinched the series on Tuesday, mustering only 30 for three in powerplay before Jos Buttler and Alex Hales did their best to keep them competitive.

"As good as the players we've got coming into our middle order, it's very difficult for them to salvage games from those positions," said Giles.

"Jos gave us a glimpse of how well he could play - it was nice to see Hales back in the runs and to play a slightly different role through the middle.

"But you're always up against it.

"We made a really good fist of it in the end, but we were 20 to 30 short from our start."

It was left-arm swing bowler Krishmar Santokie who did the most recent damage, but before then West Indies spinners undermined England.

"We're consistently having problems with spin," Giles said.

"In Bangladesh it's definitely going to play a part.

"We'd be naive and stupid to think that probably every team we come up against is not going to open up with spin against us.

"We have to try to find a formula at the top."

England have recruited Ian Bell, as a replacement for the injured Joe Root, but it is yet to be seen whether a player with almost 100 Tests and approaching 150 one-day international caps will be a Twenty20 remedy too.

In the meantime, Giles must try to give current incumbents some self-belief.

"Our message is, quite clearly, 'go and express yourselves, we back you, go and play your way'," he said.

"But I think, as much as you say that, you have to understand that guys who are struggling for runs - in the heat of battle, with options going through their head - are sometimes going to hesitate.

"If you slightly back off that option, choice, decision you're going to get into trouble."

He hopes relevant experience here can outweigh the negative impact of defeat.

"We've come up against a very, very good side," he added.

"Losing isn't great preparation but the wickets we've played on against this side are actually pretty good for where we're going and who we're going to be playing against."

In Buttler and others, if they can regain form, England do have power hitters - if not quite in the same number as the Windies.

"We can't 'magic' guys out of thin air," added Giles.

"We have to work with what we have, and I think we've got some very good players in the side.

"We're not quite getting it at the moment, but we need to keep pushing.

"We can't back off now ... at least we're trying, to get our yorkers and our skills right.

"Through the middle of the innings yesterday, we squeezed them like hell - and they looked as fragile as we have at times."

Giles' England will stick together, but have a mighty task on their hands.

"We're all in the same boat, all a team - players, management. We all operate together," he said.

"What we are doing at the moment is hesitating.

"You can't do that in Twenty20 - if you do, you're dead, sitting ducks.

"As good as (Eoin) Morgan, Buttler and (Ravi) Bopara are, leaving them in those positions all the time, you're not going to win many games - if any.

"We've been working on [those skills] - this isn't 'lastminute.com' - are we able to ingrain those skills in the next 10 days to help us win that tournament? I don't know."

Meanwhile, Stuart Broad's knee injury is causing England concern, although they remain optimistic he will be fit to lead them in Bangladesh.

Giles hopes the injection Broad had to treat his patella tendinitis will ensure he recovers in time.

"Broady is a bit more of a worry," said Giles, who also has slight injury concerns over Morgan, Buttler and Michael Lumb.

"He's got stuff going on in his knee, and we've got to manage him.

"Until we get to Bangladesh, and the first couple of games there, we won't really know.

"But we're confident."