Jonathan Agnew column

By Jonathan Agnew BBC cricket correspondent

The real focus will be on Matt Prior, especially if England do play both spinners

With everyone fit, this is the England squad we were expecting for the first Ashes Test.

With three days until the first ball is bowled, we can't yet be sure what the pitch and conditions will be like so there is the flexibility in the 13 to find the right balance on Wednesday.

There appears to be a straight choice between Graham Onions and Monty Panesar and this will come down to how England believe the pitch will play.

Any suggestion of spin, and Panesar will get the nod, despite the straight hit into the river at the Swalec Stadium - formerly Sophia Gardens - being absurdly short. If the forecast is for humid, unsettled weather, Onions will have the opportunity to continue the impressive start he made to his Test career against the curiously de-motivated West Indies.

Steve Harmison would have come very close to selection. He has had a good start to the season in county cricket, and clearly bowled well for his six wickets at Worcester.

He certainly exposed a weakness in Philip Hughes, who was roughed up in both his brief innings - but with Andrew Flintoff back in the team, England have the firepower (remember as well how Stuart Broad dealt with Ramnaresh Sarwan at Chester-le-Street?) and they need James Anderson's ability to swing the ball.

Things might change, and there's always the scope for an injury or two but, as yet, there's no room for the enigmatic paceman in this balanced attack. Ian Bell is in the squad simply as cover for injury.

The real focus will be on Matt Prior, especially if England do play both spinners. James Foster took two lovely stumpings in the Twenty20 - not brilliant, but of the standard we expect of international wicketkeepers - and this is where Prior has his work cut out.

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As always, it comes down to balance in the team, too, and Prior's batting ability makes him a solid choice for number six, and allows Flintoff to drop to seven. But a fluffed chance or two, and the pressure will mount.

So to Cardiff, which has never staged a Test before. Its sudden elevation in status over Chester-le-Street and Trent Bridge, in particular, remains the subject of much rancour on the circuit and we all hope that the venue proves its worth as host of the opening Test of this much anticipated series.

Its lack of history and track record might just help England, and should they win, the ECB's controversial decision to award Cardiff this match will suddenly seem to have been inspired.