Judging by his tan and general state of wellbeing when compared with a tired and dogged Gordon Brown, Mr Blair's appearance had all the razzmatazz of a showbiz celebrity endorsement than a helping hand from a former Labour prime minister.
It is less than three years since Mr Blair stepped down as prime minister and handed over to Gordon Brown after what had been, for long periods, a fraught and strained relationship. Mr Blair has gone to be a Middle East peace envoy and become a multi-millionaire. Mr Brown was catapulted into a global banking crisis and left with the highest levels of debt in the UK's peacetime history.
With the polls showing Labour trailing in third place behind the Liberal Democrats, many supporters must be wondering whether they were right to accept Mr Blair's hand-over to Mr Brown. Certainly, at the time, the outgoing PM was laden with all the baggage of a deeply unpopular war in Iraq and a relationship with a neocon US president that was widely perceived to be fawning. But events have moved on. Iraq has faded from the public consciousness. Public debt has moved centre stage. Might not Tony Blair, however tarnished on foreign policy, have made a better job in leading change in the public sector in a programme designed to run hand-in-hand with economic recovery?
Many of the middle-income voters who now look to have deserted Labour may well have found the arguments more persuasive and certainly so when put by Mr Blair in a TV forum where he has always been a powerful and eloquent performer. But all politicians succumb to a form of metal fatigue.
For Mr Blair to have taken Labour to three election victories – the third despite criticism over the Iraq war – was an astonishing achievement. To expect him to have stayed on to attempt a fourth is beyond credulity. He would almost certainly have lost his chancellor in a blazing denouement over breach of trust – and that may have deeply split the party.
Mr Brown's view of Labour's core purpose was never identical to that of his predecessor. And he has never been an enthusiast for the Blairite reforms of public service delivery. The result has been a premiership focused on public services, the success of which Mr Brown measures in terms of inputs – big new money in – rather than in outputs – changes in patient service delivery and a greater emphasis on parent and patient choice and service.
Circumstances now demand the most radical change in the public sector and how it operates. Mr Blair may have forged a credible centre-left realignment with the Lib Dems to undertake this task. But Mr Brown can only make this look like the desperate last throw of the dice that it is.