Go Johnson go!

Glenn McGrath has warned England to expect a backlash from troubled Australia fast bowler Mitchell Johnson in the Third Test at Edgbaston after holding talks with the out-of-form paceman.

Johnson arrived in England with a reputation as the most fearsome left-arm quick in the game, but his performances in the first two Tests were so below-par that he became cannon fodder for England's batsmen.

Johnson has become so wild that captain Ricky Ponting has little idea what is coming next and his loss of form has been blamed on anything from the position of his wrist when bowling to a tug-of-love between his mother and his girlfriend.

The 27-year-old has another chance to rediscover his rhythm in the three-day tour match at Northamptonshire, which started later on Friday, and McGrath revealed he had spoken to the Queenslander after his disappointing display in England's victory at Lord's.

Standard sport columnist McGrath said: "I had a good chat with Mitch and passed on my thoughts. I told him I had total faith in him.

"The margin between bowling badly and bowling really well is often a tiny one. As long as the attitude and mental preparation are right, everything can just fall into place.

"I tried to give him a bit of confidence. Now, it is up to him, but he seemed quite upbeat when I spoke to him, and happy with the way he batted to score 63 in Australia's second innings at Lord's.

"All he needs is one good spell, then he will be back to his best. I'm tipping him to come back with a vengeance at Edgbaston."

While the absence of Kevin Pietersen from the rest of the series will undoubtedly weaken England, Australia find themselves with more selection headaches than their opponents.

England emerged from their victory with most areas of the team working well. By contrast, Australia have huge question marks over Johnson and Phillip Hughes, the two men who were supposed to give them an instant advantage with bat and ball.

Although Johnson has not done his reputation justice in the Ashes but has been working with Glenn McGrath in a bid to get back on track.