RARELY has a politician heavily involved in an electoral triumph been so overshadowed by his own colleagues and the historical tide of events.

While Nicola Sturgeon has spent the last month with a microphone permanently stuck under her nose or sitting on the most prestigious broadcast studio couches in London, and Alex Salmond has been hounded for his intentions, spare a thought for Angus Robertson.

As The Herald first revealed, it was always the case that Mr Salmond would defer to Mr Robertson as continuing Westminster leader when he made his return journey back down to London for in his latest incarnation there.

Indeed it was always a racing certainty that the talents of all the old parliamentary group would be pressed into service when the new wave arrived, given the need for guides and mentors for the fresh intake.

But Angus Robertson deserves particular credit for his role over recent years, his election campaign, and his stoicism in the face of a media disinterested because of the obsession with Ms Sturgeon and Mr Salmond. The party's Westminster leader has been a good act when called on to the occasional television panel or debate.

He has carved out a role dealing with European media, in which he relishes making use of his fluent German, and while the key defence issue has been Trident the MP for Moray has made wider points about the UK's dysfunctional defence policy which has seen the UK bereft of maritime air reconnaissance across the North Sea.

His earnestness on these issues has seen him mocked by colleagues on occasion, but his expertise is not in doubt, and it will fall to him to ensure that a Westminster group which has gone from six to 56 will not become an inadvertent wrecking crew.

That old parliamentary group of six, plus Alex Salmond, must now become a powerful group of mentors for the new intake which includes an old foe who once threatened to sue Mr Salmond, Ross, Skye and Lochaber MP Ian Blackford, and famously a new MP who took out the Shadow Foreign Secretary, Douglas Alexander, in Paisley and Renfrewshire South, Mhairi Black, who has become the UK's youngest ever MP at the age of 20 and will have to return to Glasgow University to complete her finals.

Mr Robertson will be central to any negotiations about how the SNP functions at Westminster, how the new crop set realistic targets, how they maintain discipline, and how the group dovetails with Holyrood MSPs in maintaining a consistent wider message.

Mr Robertson was not just Westminster group leader but campaign director for the most emphatic electoral triumph in his party's history, something built on the kind of polling information and electoral metrics which he has long revelled in.

He is fully entitled to recognition for these achievements, but politics being the shallow business of today and tomorrow, but rarely the day after that, he may well find himself being overshadowed by Mr Salmond's arrival back at the Palace of Westminster, where many in the media will naturally turn to the more charismatic purveyor of the expertly honed sound bite.

But it is to the SNP's leadership as a whole that responsibility will fall for the collective discipline of this extraordinary band of new arrivals, with all the scope for pitfalls and errors under the watchful eye of a hostile media which that will entail, and Mr Robertson will bear responsibility for that.