Melbourne - Enigmatic Australian paceman Mitchell Johnson holds the key to the coming Ashes series against England, former South African Test coach Mickey Arthur said on Tuesday.
Johnson's three-year career has hit peaks and troughs and he is at the vanguard of Australia's bowling attack as they try to win back the Ashes urn lost in England last year.
Johnson had a torrid Ashes campaign last year, struggling with personal issues before finishing the five Tests with 20 wickets and going for more than four runs an over.
His tour of India last month was solid without being spectacular, taking eight wickets in the two Tests and he has been far from threatening since his return home with one wicket from the three one day internationals against Sri Lanka.
Critics point to the left-armer's struggle to retain accuracy as well as his lack of wickets as a cause of concern.
Arthur, who left the South African team after five years in charge to coach Johnson's Western Australian state side in April, believes Johnson is the man upon whom the Ashes will hinge.
Arthur well remembers Johnson's devastating spell of 8-61 against South Africa in Perth two years ago on his way to becoming chosen as the ICC Cricketer of the Year in 2009.
"The key to the Ashes is going to be how well Mitchell bowls," Arthur told the Melbourne Age.
"He's the one out-and-out strike bowler that Australia have and I've seen first-hand how good he is when he gets it right. He can win games.
"I think it's fair to say he probably is a bit hot and cold at the moment, by his own admission, but he's got that X-factor.
"He could go a spell where you're looking at it thinking, 'That was ordinary', but then he can bowl one spell that actually wins you games.
"I'm not sure if (the reason for inconsistency) is technical or mental, I haven't worked with him long enough to form an opinion on that."
Arthur said he would mentor Johnson over the coming week in the hope it would trigger a resurgence from him in WA's next Sheffield Shield match against Victoria, starting in Melbourne on November 17.
"The more Mitch bowls the better he becomes, and it's a lot like that with fast bowlers," Arthur said.
"Hopefully, we can get him firing in Melbourne, not only for WA's sake, but also for Australia's sake. I think he'll come through OK."