If the verbal vitriol being poured over its head is a clue, Nanjing Automobile must be rated a serious contender to take over the remains of MG Rover.

One person connected with a rival bid said of the Chinese company: "It is like comparing Port Vale to Chelsea."

Union leaders who seem to prefer Nanjing's Chinese rival SAIC - the group that tipped MG Rover into administration when it walked away from a proposed joint venture - allege it is planning only "a lift and shift" raid on the assets.

All the interested parties have signed draconian confidentiality agreements with MG Rover administrators PricewaterhouseCoopers and firm facts are hard to obtain.

But behind the fog and confusion that surrounds the bidding process a picture is emerging that seems to strongly favour Nanjing's plans.

In essence, these involve employing up to 2,000 in the UK to produce sports cars and premium saloons plus the final assembly of small and medium car kits shipped in from China.

Were it to go ahead, the plan would give Nanjing a production bridgehead in the western European car market but the prospect of using British workmen to produce " knockdowns" would be a bitter pill to swallow.

After all, Longbridge has a long history of shipping out kits to be assembled in countries with no car industry of their own.

But one industry insider says such a move would greatly reduce costs and enable the cars to be sold in Europe for less in a market that is becoming increasingly price sensitive. Also, quality would not be an issue. "The cars the Chinese are making either in their right or for other manufacturers have very high levels of quality," he said.

Nanjing is known to have been working on its bid with Nick Stephenson, one of the four Phoenix Venture Holdings directors who bought Rover from BMW for £10 in

2000. Behind the scenes the other Phoenix bosses - John Towers, John Edwards and Peter Beale - are also thought to favour Nanjing.

The Birmingham Post has learned that they have been providing information and contacts to most of the bidders but have no financial interest in any of the bids and will not be part of any future management team at Longbridge.

The only two serious rivals, the proposed partnership between SAIC and former Ford of Europe boss Martin Leach and the Midlands consortium headed by company doctor David James are struggling to find the cash.

Nanjing's ace seems to be that it has the most comprehensive offer on the table and it has money - thought to be in the region of £50 million - to put on the table.

And it has the backing of Ove Arup, the respected British engineering and management consultancy.

Arup employs 7,000 experts at 73 offices in 32 countries and has worked on many major projects including the structural design of the Sydney Opera House in the 1960s to the Channel Tunnel rail link.

About 300 Arup engineers work at the £7 million Arup Campus at Blythe Valley Business Park in Solihull.

Its automotive engineers have worked with most of the world's major car companies and are behind such classics as the Ford GT40 sports car.

Arup is prominent in China through its work on the Water Cube, China's new national swimming centre that will be a showpiece of the Beijing Olympics in 2008.

Despite being China's oldest carmaker - it began operations in the eastern Jiangsu province in 1947 - Nanjing is little known in the west.

It emerged only recently that it was, in fact, partnering the bigger SAIC in the abortive plan to develop a new generation of cars to be built both in China and Britain as a joint venture with MG Rover.

Nanjing was caught out by the boom in Chinese carmaking and for the past few years has been plodding along making vehicles under a small scale deal with Fiat.

In global terms the company is small: it has assets of less than £1 billion and fewer than 15,000 employees.

But its two major shareholders are also powerful operators within the Jiangsu government and so funding for a takeover of Longbridge will not be an issue.

With PwC looking to wrap up a sale by the end of the week and with the SAIC/Leach and the David James bids seemingly stalled, the chances of Nanjing taking over Longbridge are high.