Sydney, Nov 14 : Australian spin legend Shane Warne has backed fast bowler Mitchell Johnson to deliver on his bold pre- Ashes predictions, saying maturity has made the left-arm speedster more reliable.

Johnson, named in Australia's squad for the first Test of the winter series, has vowed to attack England's batsmen, particularly Alastair Cook and Jonathan Trott , with short balls directed at the ribs or throat.

According to News. com. au, although erratic line and length have generally made Johnson a boom or bust proposition at Test level, Warne believes that has changed, saying that Johnson is a bit more mature and knows his role, his body and his bowling more better this time and is going to shake the English side up.

Warne further said that Johnson, who regularly topped 150kph during the recent one-day series in India, has forced his way in through bowling some serious pace, adding that his role is going to be- go out to just bowl quick. (ANI)