Bad week for Botcher Boris as another top aide quits...

David Cameron is likely regretting his photo-op with Tory playboy tycoon David Ross now that his £130 million shares scandal has been exposed.

But doesn't the judgement of Dave's Bullingdon Club mate Boris Johnson looks even worse than David Cameron's, as the Mayor of London hopelessly tried to save yet another of his top advisers. All this in the same week as he is being investigated over his behaviour in the Damien Green affair.

The headline in today's early London Standard was

'Boris stands by 2012 aide facing probe into £130m shares scandal'

The Standard declared that Boris was 'standing by' David Ross who he had appointed to oversee the 2012 London Olympics on his behalf - despite the fact that Mr Ross faces a formal investigation by the Financial Services Authority.

A spokesman for Boris told the Standard:

'If the FSA doesn't find any fault with David Ross all we have to go on is his firm saying it's an oversight. The Mayor is not yet convinced that the case for him going is overwhelming. The crucial fact is whther they can demonstrate in any convincing way that he's messed up. If the FSA doesn't say it's more serious then it is hard for us to act'.

Labour were quick to point out that despite Mr Ross being forced to resign under a financial cloud from the company he co-founded, Boris still thinks he's an appropriate person to oversee London's Olympic budget.

Labour quickly accused Boris of being so terrified of losing yet another adviser that he was failing to see that the longer Boris failed to act, the quicker financial confidence in the Olympics would diminish.

Within a couple of hours, the Standard was changing its headline, to reflect Ross's resignation as Boris's man at the Olympics.

If a week's a long time in politics, what's a couple of hours...?

The Standard went on to report that Ross's departure is

'a major blow to Mr Johnson and prompts further questions about the Mayor's judgment.'

He is of course the fourth senior City Hall aide Boris has lost in recent months.

Boris was forced to sack his chief political adviser, James McGrath, after the former Central Office aide suggested black people should "go home" to the Caribbean if they did not like living in Tory-controlled London.

Then his deputy mayor Ray Lewis - hailed as a champion by David Cameron - was forced to resign after allegations over 'financial irregularities and inappropriate behaviour'.

And then Tim Parker, another of Boris's deputy mayors who also served as chair of Transport for London, bcame the third of his senior team to quit in controversial circumstances.

Is this Boris's worst week so far as the most high-profile elected Conservative in the land?

I suppose it could be worse for David Cameron, pictured in most of today's newspapers with the fallen tycooon at a Tory social event: A Independent profile of Mr Ross suggests that he was considered as Tory candidate for Mayor of London...!