George Bailey will lead Australia against England tomorrow, in the absence of Michael Clarke, in his first game since playing for Hampshire.

Clarke, who played for Hampshire in 2004, is unavailable because of his ongoing back problems, so Bailey takes over for his first competitive match since making 84 against Lancashire at The Ageas Bowl a fortnight ago.

Bailey, who has made 21 and 1 in Australia's two warm-up matches, said: "There's no doubt it's a blow, we'd love to have 'Pup' with us as a batsman and as our captain.

"But it is what it is, and we have to deal with the fact that we don't have him for tomorrow."

Bailey believes, however, that Clarke's unavailability provides extra motivation for his team-mates to prove they can overcome the setback.

"The challenge is there and the opportunity is there for the rest of us to step up, and I know it will be a great boost to the side to know that we can win without him," he said.

"We had to do it quite a bit over the (Australian) summer in the one-day format, so we know we can."

Australia know nonetheless they need Clarke fit again as soon as possible - initially for their remaining two Group A matches in the Champions Trophy, and for the Ashes beyond.

"He's desperate to play in this tournament, then going forward one-day cricket as well," Bailey said.

"So he's doing everything he can."

Alastair Cook believes all is not necessarily "doom and gloom" for Australia, despite the injury-enforced absence of his opposite number.

Cook, who has suffered himself in the past with back pain and even had to miss England Lions fixtures for that reason, points out Australia have strength in depth to cover for their captain.

"Obviously, when you lose a player of that stature and that quality, it would be a loss to them," he said.

"But they've got a good squad and some fine replacements.

"I don't think it's not all doom and gloom for them, but losing your captain is tough."

England, meanwhile, expect to be able to pick from a full 15 - including Tim Bresnan, whose wife was due to give birth to their first child on Monday but has yet to do so.

"He's still here," Cook said.

"I had coffee with him an hour ago. So that's not changed in the last hour or so - he's still with us.

"Clearly your best-laid plans go out the window in terms of obviously the family comes first.

"I think that's always right, no matter how big the game is or how big the tournament is.

"We hope Mrs Bresnan can hang on so we can have a couple of days off and we can pick from our 15."