Australia's three major iron ore producers, BHP Billiton, Rio Tinto and Fortescue Metals, are feeling the pressure of the slump in the commodity's price this year. During the past week all have gone on the offensive to convince the investment community that the problems are not of their own making, and that they have strategies to mitigate the downside to earnings.

With the price in freefall, investment banks and their commodity experts are updating their outlooks at increasingly closer intervals. At the start of the year the general consensus – to the extent there is one – was a price of about $US100 ($119) per tonne, they are now closer to $US70 a tonne. The outlyers are far lower. For the most part this exercise is not rocket science, rather the forecasters are just following the price down.

The same goes for the producers. None were predicting anything like the current price nine months ago. The reality is that neither the commodities experts nor the companies that dig up iron ore have any real idea where the price will ultimately land.

At current iron ore prices BHP and Rio might be fairly valued or indeed undervalued. But investors aren't taking the bait and are instead viewing the reliability of the earnings from these companies as more of a crap shoot.

Thus it falls to the miners to provide investors with some degree of certainty around their returns despite the unpredictability of revenue.

Rio Tinto was the first cab off the rank last week. It held an investor briefing to convey the central message that its promise to reward shareholders with some kind of capital management program was still on track.

It was unequivocal about the fact that there would be a present for investors – albeit not one timed for this Christmas.

So how will this be funded? Until recently the idea is that it would come exclusively from cash flow. But with the analysts crunching the numbers on how the iron ore price plays into the equation, the new collective intelligence is that Rio Tinto may have to use its balance sheet – which it has been assiduously and successfully attempting to improve – to fund the promised investor goodies.

For example the UBS view is that, "Under our base case, we expect Rio Tinto to generate [about] US$2.1billion free cash flow in 2015 post an assumed 10 per cent increase in the dividend, which in our view may be considered a material increase in itself. Under spot pricing, however, free cash flow reduces to [about] $400m. While this looks like a significant decrease, we believe that by increasing gearing from the current 22 per cent to 24 per cent, Rio Tinto could increase its free cash flow to [about] US$3 billion".

Rio's other lever in the shareholder return-balance sheet balancing act is to reduce its capital spending and continue to reduce its costs.

After promising to spend about $US11 billion on projects at the start of the year, it is now on track to spend $US8.5 billion in 2014.

Friday's briefing made it abundantly clear that it would need all these weapons to get the result.

And in Rio's case there is additional pressure to reward shareholders given it is being stalked by the aggressive predator, Ivan Glasenberg's Glencore. While Rio Tinto has ostensibly rebuffed its suitor, any disenchantment from Rio shareholders makes it more vulnerable.

Similarly, BHP Billiton has made promises to its shareholders to at least hold the current dividend in the face of pressure on profits. It doesn't have a predator to contend with but it does have the additional headache of the large-scale fall in the price of another of its products – oil.

Where BHP and Rio arguably have some supply, and therefore price, control in the iron ore market they dominate with Brazilian Vale), in the oil market in which BHP also plays, it has less control even though it is a sizeable part of the US shale oil production revolution, which is producing a supply glut.

Last week's decision by the OPEC cartel to maintain supply, rather than cut it in the face of falling prices, certainly didn't help. The result is that BHP is fighting fires on two sides.

While consumers worldwide celebrate cheaper fuel, producers suffer the financial consequences of a fight for market share.

The parallels between the OPEC cartel in the oil market and the iron ore producers that dominate supply – but cannot collude on production – are hard to miss.

BHP and Rio have been roundly criticised for stepping up iron ore supply in a softening market and it's an issue on which there is plenty of sensitivity.

Despite some shareholder and West Australian government backlash, both continue ramp up production and achieve healthy margins. It fell to BHP's iron ore boss, Jimmy Wilson, to defend the company strategy in the media at the weekend, saying pulling back production would damage shareholders.

While it needs to adhere to the promise to retain dividends, there is no longer any suggestion it will reward shareholders with capital initiatives.

Fortescue, whose fortunes are even more closely tied to the iron ore price, has little choice but to cut a swath through its costs and capex – the plans for which it delivered to the market late on Friday. The perennial underdog, Fortescue lays the blame on its predicament at the feet of the big boys in iron ore. Whether this is fair or not, the fact is that Fortescue's higher cost base – due primarily to its bigger debt load – make it most vulnerable and desperate.

The demand side of the oil and the iron ore equations are exacerbated by the weakening growth out of China, which is struggling to meet its stated GDP growth projection of 7 to 8 per cent this year. And there is no argument over the fact that they are powerless to influence this demand.