Six weeks into the job, NHS chief executive David Nicholson has had a few days in which he will have felt the full force of the pressure he must withstand in his role at the centre of the increasingly heated debate about the future of the NHS.

Six weeks into the job, NHS chief executive David Nicholson has had a few days in which he will have felt the full force of the pressure he must withstand in his role at the centre of the increasingly heated debate about the future of the NHS.

On Monday he entered the bearpit of the Commons public accounts committee to explain his progress on erasing the NHS deficit. It is the kind of arena in which, in the closing weeks of his stewardship of the health service, the lacklustre performances of Sir Nigel Crisp provided evidence of his waning influence.

Mr Nicholson, by contrast, was much more effective and combative. He stuck to his predictions of a surplus at year end and didn't fall into the trap of defending poor financial performance. His line was that some of it was bad, but we are doing something about it.

Perhaps the strength of his performance in front of MPs led him to believe that Tuesday's Downing Street press conference with Tony Blair and chief medical officer Professor Sir Liam Donaldson would be easier (news, page 6). But he stumbled over explanations of job losses when he could easily have quoted NHS Employers' own estimates that original fears of threats to 20,000 NHS posts have boiled down to just 766 redundancies so far (news, page 9).

He wasn't helped by, and took some of the blame for, a presentation by the CMO that appeared to explain away hospital rationalisation and job losses purely in terms of advances in medical technology.

Mr Nicholson said he wants to move the debate on from the number of hospital beds and the 'saving' of hospitals. That won't be achieved with one press conference, but his success will be the defining feature of his first year in the job.