Australia captain Michael Clarke was upbeat on Thursday about Ryan Harris’s prospects of featuring in the fourth Ashes Test starting on Friday despite the paceman’s poor fitness record.

Tasmania quick Jackson Bird was added to the Australia XI that delivered a much improved performance in the drawn third Test at Old Trafford when the tourists named a 12-man squad on Wednesday for the Chester-le-Street Test.

With Australia 2-0 down with two to play, and so unable to regain the urn, there are those who argue now is the right time to give the twice-capped Bird his first taste of Ashes action.

Too important

But Clarke said Tests were too important for anyone to just be “given a go”.

As for the 26-year-old Bird’s prospects of being selected for his first Test appearance since facing Sri Lanka at Sydney in January, Clarke said he would be treated like anyone else.

“I don’t think anyone is here to ‘give them a go’. That's not in any Test cricket and certainly not an Ashes series, especially the position we’re sitting in now. It’s about picking your best 11 players.”

Meanwhile, England captain Alastair Cook insisted the fact that England had retained the Ashes in 14 days had not diminished its hunger to win the series.

“We want to go on and win the series. The way the lads are, the way we are as a team and the way (England coach) Andy Flower operates, there will be no let up of the standards we set ourselves,” said Cook.

Not complacent

And Cook said the fact Australia upped its game in the drawn third Test at Old Trafford would help England guard against complacency.

“We start from scratch. We keep saying what a good side Australia are and Old Trafford showed that.”

Cook, the only England batsman to have scored 25 Test hundreds, dominated the 2010/11 Ashes with 766 runs at an average of 127.66 and three centuries with a best of 235 not out.

However, the 28-year-old left-hander has found runs harder to come by this series with Cook having so far managed a meagre 145 runs in three Tests at 24.16 with two fifties and a best of 62.

“Form is one of those things that is a bit of a mystery,” he said.

“I don’t feel as if I’m doing too much wrong; obviously I’d like a lot more time out in the middle and some runs, but I can only back the fact that I’ve done it in the past and hopefully I can do it again in the future.

“I’ve scored (more than) 7,500 Test runs and been around a while. I’ve had these little dips in the past and come through them.”

The teams (from): England: Alastair Cook (capt.), Joe Root, Jonathan Trott, Kevin Pietersen, Ian Bell, Jonny Bairstow, Matt Prior (wk), Tim Bresnan, Stuart Broad, Graeme Swann, James Anderson, Graham Onions, Chris Tremlett.

Australia: Shane Watson, Chris Rogers, Usman Khawaja, Michael Clarke (capt.), Steven Smith, David Warner, Brad Haddin (wk), Peter Siddle, Mitchell Starc, Nathan Lyon, Ryan Harris, Jackson Bird, Ashton Agar.

Umpires: Aleem Dar and Tony Hill. TV umpire: Marais Erasmus. Match referee: Roshan Mahanama.

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