England have challenged reborn Australian fast bowler Mitchell Johnson to prove he can sustain his firepower for the duration of a test match.
The West Australian left-armer has fought his way back into Ashes cricket after his deflating performance against England in 2010/11.
Ahead of Thursday's first test in Brisbane,those in the know say Johnson is armed with a new mindset and an improved action.
In recent one-day tours his pure speed has proven tough to handle. But England fast bowling coach David Saker warned success with the white ball is not test domination.
Saker said Johnson would need to show he could put effort on effort.
"His one-day form's fantastic. He obviously played some good cricket over in India," he said.
"But we all know that one-day cricket and test cricket, there's a big gap between red ball and white ball.
"You've got to be out there for 25-30 overs, which can be different. If you've just got 10 overs to go you know what you can do. But his form's been good, it's been encouraging for them."
Meanwhile, Saker says Australia are welcome to try to attack champion England spinner Graeme Swann, but it will be at their peril. The Australians have outlined a plan to try to get after Swann this Ashes series and not allow him to settle.
Saker said Swann is a matchwinner in all conditions.
"He's done it on all surfaces around the world and he's done it really well for us," Saker said.
