SCOTTISH LABOUR'S new spin-doctor made a series of damning criticisms of his colleagues weeks before he accepted the job as the party's head of communications. Gavin Yates used his blog to describe Wendy Alexander as "abrasive", labelled shadow health minister Andy Kerr as "simply uninspiring", and blasted Jack McConnell for being a "lame duck leader" when in office.

He also said the fledgling SNP government had a "long and impressive" list of achievements, while describing first minister Alex Salmond as "a great example of a politician on top of his game".

The online blasts are the latest PR disaster for Alexander who, as Labour's newly appointed Holyrood leader, has watched two spin-doctors quit in as many months.

The first press aide, Brian Lironi, quit his post in September, days after she had been formally installed as leader.

Then her media chief, Matthew Marr, resigned in disgrace eight days ago after shouting the c-word at Salmond during an awards ceremony.

Alexander is set for further embarrassment after it emerged that Yates - the Labour group's new head of communications - attacked his future bosses weeks before accepting the new job.

His comments featured on his WordPress-hosted blog, GYmedia. A message on the blog page now states: "The authors have deleted this blog. The content is no longer available."

But the Sunday Herald has uncovered a number of Yates's postings, many of which portray the Labour leadership in a negative light.

On Alexander's speech to the UK Labour conference in September, one of his internet postings states: "New Labour leader Wendy Alexander was rather less positive, using her conference speech to apologise' for losing the last election in Scotland. Rather odd: and certainly doesn't bode well for her renewal agenda.

"The news yesterday that her spinner-in-chief Lironi had resigned after a month, to be replaced by a man who ripped up his party card a few years ago, does not augur a speedy return to government either."

The same entry, which was made days after Alexander became leader, saw him aim a jibe in her direction: "As Gordon Brown considers taking the biggest political risk of his life, the Scottish government can go along unhindered by a competent opposition."

In a commentary on Scottish Labour in July, when Jack McConnell was on the verge of quitting, he blogged: "Next, what happens to the Scottish Labour Party? Wendy Alexander, a former minister who fell from favour with the so-called Labour West-Coast Mafia' is in pole position but her abrasive style might not prove popular with everyone. Also, she is seen very much as a Brown acolyte and that won't go down well with MSPs that want a separate Scottish Labour identity from Westminster."

On the possibility of East Kilbride MSP Andy Kerr replacing McConnell, he said: "The other front runner looks to be former health minister Andy Kerr. He's seen by some as effective but by many others as simply uninspiring."

On current deputy Labour leader, Cathy Jamieson, he said she was "left looking impotent" when dealing with the subject of airguns as a minister.

Yates, 39, also had a dig at the prime minister, of whom he said in August: "Under Gordon Brown we have the greatest disparity between the richest in our society and the poorest."

In September, he turned his fire on former Labour first minister Henry McLeish, ironically for the sin of criticising his party. "His last book sold less than he - and his publishers - had hoped. And I don't think that this barrage of spinning will help him shift many more units," he wrote.

Another Labour MSP to incur Yates's wrath was Duncan McNeil, who has taken a tough stance on drug addicts having children. The blog entry stated: "More needs to be done to ensure that there are routes out of prostitution and drug abuse. Not in the way that Labour MSP Duncan McNeil suggested with his Take the kids off them and feed em contraceptives in their methadone', but in the way that Sacro have been working in Edinburgh."

By contrast, Labour's new spin chief made a number of positive comments on Salmond and the SNP government.

On the first minister's handling of the "national conversation" on independence, which Labour criticised, Yates said: "His pincer movement with the white paper yesterday is a great example of a politician on top of his game."

Responding to commentator Neal Ascherson's upbeat remarks on the Nationalist administration, Yates wrote in August: "There is already a long and impressive list of SNP achievements in its first days as Neal sets out."

"Meanwhile, Labour find themselves still stuck in a post-electoral malaise with a lame-duck leader."

He added: "The SNP go from strength to strength as Scots witness a post-election honeymoon. However, it might be more to do with Labour's inability to land a blow rather than the particular merits of the new administration."

One senior Labour insider said Yates's blog came at a bad time for Alexander: "You would think the party would make checks on the people they hire. Wendy is struggling, and the last thing we need is another piece of nonsense like this."

Another party source said: "She's not had a great start. This is not helpful."

Yates's non-political comments are bizarre rather than controversial, such as his musings on the postal service: "This might sound like hyperbole but Royal Mail should be viciously broken into tiny pieces and fed to its chief executive anally."

On Royal Mail informing him of the benefits of sending items second-class, he said: "So that's the official line from Royal Mail - to stop busting your budget publishers should offer a second-class service. Talk about being buggered."

He also claimed the London Olympics would not benefit ordinary Britons, even mocking some of the events: "The 50km walk consists of people walking along as if they have a bit of super-strength chewing gum shoved up their bum and they have to get all the flavour out before they finish."

Yates used to work as a communications manager at the Scottish Council for Voluntary Organisations. He is set to start the £40,000-50,000 post in December.

Labour's new spin chief said yesterday: "My comments have been taken out of context. I wrote them as a journalist in July and they do not reflect my own views. I think Wendy Alexander is a winner as is Andy Kerr."

A Scottish Labour spokeswoman declined to comment.