TODAY is the day that Chancellor Alistair Darling will wish he had remembered a popular saying in business school – under-promise and over-deliver.

It is bad enough to be delivering the “Budget from Hell”, owning up to the deepest recession since World War Two, and a decade-long slog to pay off all that frightening debt.

But what will make it particularly painful for Mr Darling is the stark contrast with the picture he painted back in the autumn, when he sent us all on a £20bn spending spree to keep the downturn short and shallow.

Ah, remember those days? When Britain was “best-placed” to fight off recession and the economy would be bouncing back to growth before the shadows lengthen in late summer.

Mr Darling will not wish to be reminded of the predictions made in that pre-Budget report, but he will have them thrown back at him by every Opposition speaker today – so here they are.

Back in the autumn, we were told the economy would shrink by about 1% this year. That depressing figure has long since been scrubbed out – to be replaced by 3%, or even 3.5%, today, in a recession to last all year.

Then there’s borrowing. If you thought the prediction of £118bn this year was scary, prepare for £160bn or £170bn today. Debt was already due to peak at more than £1 trillion, but will now be even higher.

Mr Darling’s embarrassment matters, because it points to a wider truth about what – apart from the Home Secretary’s greedy expense claims and the sickening No.10 smear campaign – is dragging down Gordon Brown.

It is the way the Prime Minister and his Chancellor have repeatedly promised that recovery is in sight and help is at hand, even while the jobless count and home repossessions tally soar.

Mr Brown still deserves credit for the Great Bank Rescue, but the story since has been one of eye-catching initiatives announced with great fanfare, but still not actually delivered on the ground, where it matters.

The moribund car industry is still waiting for help to arrive, few big capital schemes have been brought forward, and struggling mortgage payers only finally got help from yesterday – three months late.

The lesson is not to over- promise and under-deliver – as Mr Darling will find out today.

* SPORTS Secretary Andy Burnham had to apologise to MPs on Monday for being “a touch croaky” after cheering on his beloved Everton to cup semi-final triumph over Manchester United.

He also admitted to a “rift in the department”, confirmed by a grumpy-looking Gerry Sutcliffe alongside him. The sports minister is an Old Trafford fanatic.