There is only one real winner in this cabinet reshuffle: Gordon Brown

Mr Blair's prestige has suffered considerable damage, but he has seized the opportunity to make the best of a bad job

Excuse a certain smugness after I suggested on Tuesday, before any knowledge of events about to unfold, that continuing speculation about Stephen Byers until the summer recess would lead to administrative paralysis.

Mr Byers' eventual recognition of the dismissal to which he would inevitably have been subjected has enabled Mr Blair to seize the initiative and should enable the Government to enter a period of political tranquillity. Next week, with the World Cup and the golden jubilee taking over from politics, the new ministers have a chance to read themselves into their briefs while attention is elsewhere.

But for the time being, Mr Blair's prestige has suffered considerable damage. At last he seems to have recognised that those who live by spin die by spin. In less than two years he has lost Peter Mandelson and Mr Byers – the arch practitioners of this dubious art that served him so well in opposition but that has become thoroughly corrosive in government.

Mr Blair has at least seized the opportunity to make the best of a bad job, and his decision to move Alistair Darling to Transport will be generally welcomed. Mr Darling is a quiet Edinburgh lawyer who has risen without trace to become one of the Government's safest pairs of hands. He was the youngest cabinet minister in 1997 when he became Chief Secretary to the Treasury at the age of 43; he was then promoted to Work and Pensions (formerly Social Security) in 1998.

Given that the normally dry subject of pensions has now turned into a potential political nightmare, Mr Darling has managed to tiptoe his way around this minefield with a quiet competence that has ensured the issue has not become – as it deserves to be – a full-blown row. His biggest achievement was steering through the new stakeholder pensions although the take-up has been disappointing.

There is little Mr Darling can do to improve transport in the short-term, but if he can remove the issue from the headlines, that alone will be an achievement. It is unlikely there will be any sudden shift of policy, although his new broom will give him an opportunity to amend the so-called 10-year transport plan in the light of the savaging it received from the select committee last weekend. He is unlikely to reverse the controversial public-private partnership for the London Underground and will doubtless run into early trouble with Ken Livingstone. And he can also expect some flak as a Scottish MP responsible for transport in England – but not in Scotland.

Mr Darling will be the sixth of Mr Blair's Transport Secretaries – there have been 20 since 1979. Let us hope that this morning's predictable "Hello Darling" headlines are not replaced too soon with "Move over, Darling". The Prime Minister cannot afford another change at this department this side of the next election. And I have lost count of the number of times that the Transport Department has been free-standing or amalgamated with local government. This time it has had its responsibilities separated yet again; this really must be the last occasion in which it is reorganised.

It does make sense for John Prescott to take back the local government responsibilities to add to the brief he already holds for the regions. I suggested last month that Mr Prescott was in line anyway to be given a stronger role across government departments. This has come to fruition with a more formalised structure and the creation of an Office of the Deputy Prime Minister. His recent White Paper proposals for regional government carry massive implications for the future structure of local government and prove how necessary it is to have a minister who can co-ordinate both local government and regional policy.

The other big winners from this reshuffle at cabinet level are Andrew Smith and Paul Boateng (both predicted here on Tuesday). Mr Smith follows Mr Darling down the well-worn path from Chief Secretary to the Treasury to Work and Pensions, while Mr Boateng stays at the Treasury but now has his big break inside the cabinet room.

Mr Boateng has made history as the first black cabinet minister; that, in itself, will provide as many eye-catching headlines this morning as Mr Darling's appointment. But Mr Boateng is no "token" black. "My colour is part of me but I don't choose to be defined by my colour" was how he reacted yesterday when he gave his first interview following his promotion. He has been knocking at the cabinet door for some time and was due for promotion regardless of his colour or recent events.

He has travelled a long way from the days when he was a young lawyer and left-wing member of Ken Livingstone's Labour group on the old GLC. He chaired the police committee, denouncing the use of the old "stop and search" powers. Even on the night that he became one of Britain's first black MPs when he took Brent South, he was still firmly in the firebrand radical camp of the Labour Party; he declared in his acceptance speech: "Brent South today, Soweto tomorrow." Little did he think then that he could have also said "tomorrow the Cabinet". Mr Boateng will be tested immediately, as he has just a few weeks to prepare the ground for the comprehensive spending review to be announced by the Chancellor before the summer recess.

But the biggest winner has to be Gordon Brown, who has seen three of his protégés promoted around the cabinet table. Mr Darling, Mr Smith and Mr Boateng are firmly Brownite. With Mr Boateng by his side, and Mr Darling and Mr Smith both having previously served him as Chief Secretaries to the Treasury, the Chancellor can afford to be relaxed as he contemplates the state of the Blair/Brown axis.

Having such friends can cause its own problems, however. Will the new Secretaries of State for Transport and for Work and Pensions get their way when they lobby for more resources? Sometimes the old pals act can work, but on other occasions these spending ministers run the risk of being rebuffed on the grounds that they, as former Treasury men, should know better.

Further down the line, however – and there is a long tail to this reshuffle, insofar as it affects the junior ranks – Blairites will have received encouragement with the promotion of 29-year-old David Lammy – another black MP – and David Miliband, who worked in Downing Street until his election to Parliament last year. And proof that there is still life after a sacking comes with the restoration of Mike O'Brien.

When governments are in trouble, reshuffles alone rarely make much difference. Nine years ago today I received my first telephone call to march up to Downing Street to collect my job as a government whip. I was the last in the consequential moves that John Major made after he parted with Norman Lamont. But Mr Lamont's removal did nothing to refresh that Government. Whether Mr Byers' removal will do the trick for Mr Blair remains to be seen.

mrbrown@pimlico.freeserve.co.uk