Nixon said: "We need Michael with us, that's crucial and hopefully he will play every game and see us through.

"But with the amount of injuries he has had over the last couple of years he's going to have a little bit of doubt."

Vaughan will not play a full part in England's first warm-up game on 5 March as he eases himself back to fitness.

He is confident his hamstring problem will have sorted itself out before England's first World Cup match against New Zealand on March 16.

But he will not fully test it until England's final warm-up, on March 9 against Australia.

Nixon said Vaughan, who has played just three of England's last 35 one-day internationals, would not play if he was not fully fit.

"He'll make sure he's 100 per cent if he goes out and plays the first game," said the 36-year-old Leicestershire veteran.

Nixon said the two weeks between returning from the Australian tour and Friday's departure for the West Indies had been "pretty manic".

Speaking to BBC Five Live, he went on: "I've loved every minute of it. My feet haven't touched the ground.

"The media seem to have latched onto this old bald bloke from Cumbria who keeps wicket and bats, so it's lovely.

"But I've been training hard and have had some benefit work to sort out.

"Now I've got to make sure I do my job for England in the World Cup -- that's all I am focusing on right now."

England's first opponents in the Caribbean, New Zealand, are familiar opposition.

The two teams shared two wins apiece in the four matches they played against each other in the Commonwealth Bank Series in Australia.

England went on to beat Australia in the finals of that series, before New Zealand swept the injury-hit Aussies 3-0 on home soil.