On his day, Mitchell Johnson is the most destructive cricketer in the world.

Over 10 sessions in Perth he secured match figures of 9/82 in a celebration of hostile fast swing bowling. He also smashed a game-changing 62 with the bat and displayed the kind of old-fashioned fast-bowling mongrel that galvanises teammates and frightens opponents.

In the remaining four matches of an otherwise dismal summer Johnson has taken just five further wickets and scored just 60 more runs. Of those five wickets, the three immediately following his Perth haul (two in Melbourne and one in Sydney) were poorly played top-edged pull shots caught at fine leg. Of the other two, one was played on from well outside off-stump and the other came with the score at 6/487.

Johnson's career has been marked by an expectation that at any moment he could spark into life and rip an opposition apart. He has done this five times in his career. Twice against South Africa (Perth, December 08, Johannesburg, February 09) twice against New Zealand (Brisbane, November 08, Hamilton, March 10) and once against England (Perth, December 10).

The consequence of such scintillating performances is that he is unrealistically expected to bowl at 150kmh and swing the ball like a boomerang. If he can do it once (or five times) why can't he do it every time? Johnson is no longer measured against the standards of an average Test bowler; he is measured as a former ICC Cricketer of The Year.

A return of one match-winning performance in eight is not horrendous. Especially, if like Johnson, you manage to keep taking regular wickets when not operating at peak performance.

The problem for Johnson has been that those around him have also not performed at their peaks and individual and collective failings have become magnified.

When Johnson entered the Australian side he operated alongside a Brett Lee in the best form of his career and the metronomic Stuart Clark. As his status in the side grew, Lee and Clark, Andrew Symonds as well as a couple of international quality spinners departed. Their replacements, principally Ben Hilfenhaus, Peter Siddle and Nathan Hauritz have simply not operated sufficiently as a unit often enough.

It is of crucial importance that Johnson bowled best this summer in his one performance alongside a fully fit Ryan Harris. The pressure was off Johnson to perform miracles as he had a more than able sidekick to play the enforcer's role. He simply ran in and bowled like he didn't have a care in the world.

Likewise, in his other major hauls he was handed the ball later than Brett Lee in three of them and after both Harris and Doug Bollinger in the other.

As Australia's performances have dwindled, it has looked forlornly to its tall, aggressive, wicket-taking fast bowler to keep it afloat. Unfortunately, this particular version of the angry speedster does not perform at his best front and centre. He needs a sidekick or two and Siddle and Hilfenhaus (et al) have not provided that foil.

It is frustrating to imagine how Johnson might have performed had Lee, Harris and even Doug Bollinger not been so consistently injured, forcing the reluctant leader to take centre stage when he so clearly preferred the shadows.

As Australia looks to rebuild, it must take this factor into consideration when appraising Johnson. Perth apart, he has not merited his inclusion and if another fast, aggressive foil is unable to be found to compliment him, his value to the side is unlikely to be much. If however one of the young bolters can take up the mantle, or Bollinger or Harris proves their fitness, Johnson could well be the match-winning weapon to ease Australia's transition and help a crop of younger players develop in a competitive side.