EVEN allowing for the relentless barrage of crossfire in this Rangers scandal, no-one was likely to miss the explosive impact of the 1494-word grenade hurled by Dave King yesterday.

King had plenty to get off his chest about Craig Whyte, about Whyte's lawyers Collyer Bristow, and about Rangers' elusive company secretary Gary Withey – not to mention some warm hugs for those lovely folk at Her Majesty's Revenue and Customs – but there was no mistaking the man who was at the centre of his crosshairs.

Sir David Murray used to be untouchable for anyone at Rangers. King became the second boardroom figure to turn on him in the space of six days. Hugh Adam intended to implicate and embarrass Murray last week by alleging that, for years, Rangers deliberately misled the Scottish Football Association and Scottish Premier League about undisclosed player payments. That has landed a couple of inquiries on Murray's doorstep and he will have to come up with answers but, if King has his way, he will have to cough up a huge amount of money too. King put £20m into Rangers in 2000 and he now believes he was persuaded to invest under false pretences. Yesterday he accused Murray of taking decisions and committing to deals without telling him or others on the board. King versus Murray has suddenly become a huge sub-plot to the Rangers story.

King has just conducted his own fact-finding visits to significant figures in this escalating drama and he didn't like what he heard. He claimed to have only just become aware of things he should have been told about years ago, and says he only learned "the true nature" of Employee Benefit Trusts towards the end of Murray's ownership, which ended last May. Some will see that as a very questionable attempt to distance himself from something damaging that was going on while he was on the board – the use of EBTs was signed off and included in Rangers' annual accounts – and, to be blunt, there is plenty to be wary about when it comes to King.

He admitted to wanting "direction" from the SFA, which sounded as if he was not entirely sure that he would meet their "fit and proper person" criteria, which is strange given that he's been on the board since 2004. No wonder he was up front about inviting an SFA investigation upon himself: after Murray and Whyte, the one thing Rangers fans will demand from another new owner – especially if they're being asked to pump their own money into a share issue – is transparency. King's financial history is a tangled, controversial mess.

Until Whyte arrived on the scene, there wasn't a more shady character in Rangers' recent history: the South African Revenue Services (SARS) has 322 charges against him including tax evasion, fraud, racketeering and money laundering. It all started in 1998 and, despite varying attempts at prosecution or settlement, it hangs over him still.

King said he would be "guided" by the SFA's response in terms of whether he would be more involved under a new owner than he was as a non-executive director under David Murray and Whyte, but the very fact Paul Murray is having to assemble a consortium and potentially raise money from a share issue to supporters says it all about whether King's reputed fortune – estimated to be around £200m – is available to Rangers.

Two years ago it emerged that King's shareholding – the second biggest at the club – was in the name of his now 80-year-old mother Agnes, a widow living in a detached house in Alexandria, Dunbartonshire. The South African authorities believe the transfer of assets to his mother was a ploy to avoid paying taxes. Saying nothing about where he stands with the South African tax authorities was a glaring omission in King's otherwise sweeping statement yesterday.

Still, there's no doubt that adds another level of intrigue and suspicion to King's involvement but it's true, too, that he has the ear of the major players around Rangers. He has had recent meetings with Whyte, Ally McCoist, Paul Murray, Withey – twice, when most people trying to ask questions of him cannot get a hold of him at all – and Sir David Murray's business associate Mike McGill, himself a former Rangers director. King does not believe the Murray Group was aware that Whyte intended to buy Rangers through the Ticketus deal and believes the deal wouldn't have gone through if they'd known that. But any exoneration from blame ended there.

In every other sense he was aggressive and challenging about Murray: the club was much worse off because he sold it to Whyte, he felt "deceived" by Murray, and he encouraged others to consider legal actions of their own, saying "other shareholders may feel deceived like I do and wish to take similar action".

It'll never come to court, of course. Neither King nor Murray have any appetite to start mud-slinging in a court case. The tone of Murray's response yesterday didn't suggest there was much chance of King receiving any out-of-court payment either but an eventual, low-key settlement would appear the most likely outcome.

But in essence what King was saying yesterday was that if he'd known about the full implications of the EBTs, he wouldn't have touched them with a bargepole. It was a deliberate and calculated move to distance himself from the old David Murray regime in order to appear acceptable as part of a Paul Murray reign. In that regard his soft-soaping of HMRC bordered on comical. "I wish to commend HMRC for showing the maximum restraint with Rangers. The empathy that HMRC has demonstrated to the club and its fans is particularly gratifying given the abuse perpetrated on HMRC by Craig Whyte".

Murray, King and their "Blue Knights" effectively need to agree a settlement figure with HMRC to own Rangers without the club going through liquidation. King's line for the taxmen amounted to him saying "please go easy on us, give us a fighting chance."

The headlines will be about King's attack on David Murray. Between the lines, though, it was a declaration that he wishes to plant himself at the centre of Rangers' future.