Mr Parton is a telecoms veteran

As chief executive, Mr Parton will bear the brunt of Marconi's PR offensive, as the firm attempts to charm the City into supporting the new management team.

Under Lord Simpson, Marconi acquired a reputation for being aloof and out of touch - a factor that contributed heavily to its recent share-price collapse.

That will have to change.

But some doubt that Mr Parton has the credentials to impress hard-nosed bankers.

He is a long-term Marconi insider, first joining the firm - then called GEC - in 1980, and rising through the ranks to end up as head of its core networks division.

Telecoms gamble

Mr Parton certainly does not lack industry experience.

But the mere fact of his close involvement with the company, as it made its ill-timed foray into the telecoms business, may count against him.

As boss of high-tech division Marconi Communications during the 1990s, he has become indelibly associated with the telecoms gamble.

As recently as the end of last year, Mr Parton was bullishly promising that the firm would create 5,000 jobs at a new high-tech facility in Ansty, near Coventry.

Now, with thousands of existing jobs being slashed as the firm goes through the agonies of a top-down review, Mr Parton's Ansty ambitions have evaporated.

Tough at the top

Mr Parton, who has so far refused to talk about his chances of success, could be forgiven for a few first-week nerves.

The fact that Lord Simpson, until recently pugnaciously optimistic about the firm's future, chose to quit earlier than expected is being seen as an indication that his successor will face an unpalatable battle.

A glance back through business history indicates that turnaround bosses, brought in to fight crises, do not tend to last after the crisis passes.

The City is not exactly cheered, either.

Marconi shares fell by another 12% on Wednesday alone, as a swathe of investment banks again cut their ratings on the company.

Pillar of the establishment

Mr Bonham, who is serving as chairman until a full-time replacement can be found, is far better-known in the City.

Mr Bonham is the ultimate City slicker

He cut his teeth as the right-hand man to Lord Hanson, the 1980s corporate raider who built up, and then split up, one of Britain's most successful conglomerates.

After leaving Hanson in 1997, Mr Bonham became a pillar of the British financial establishment, serving on a number of corporate boards.

He is currently chairman of Cadbury-Schweppes - only the third non-member of the Cadbury family to serve in that role - and Imperial Tobacco, which was formerly part of Hanson.

Until earlier this year, he was a non-executive director at healthcare giant GlaxoSmithKline, but left in March after shareholders complained of his links with the tobacco industry.

Once a raider...

Mr Bonham's corporate-raiding days are not yet over, however.

In 1998, he and a former Hanson colleague took over Fieldens, a dormant tractor-tyre company, which they planned to use as an investment vehicle for takeovers.

Although Fieldens has yet to spark any deals, another former Hanson executive joined the firm in August, and press reports speculate that it is about to launch a flurry of activity.

Mr Bonham is believed likely to step back into a non-executive role at the firm, if his Marconi duties become pressing.

As things stand, those Marconi duties look likely to be very pressing indeed.