As a tie-up between trader Glencore and miner Xstrata is hammered out in coming days there is plenty of scope for hard bargaining between the two sides' highly competitive South African bosses.
Glencore's Ivan Glasenberg and Xstrata's Mick Davis -- both hard-driven, keen sportsmen who climbed the corporate ladder in the South African coal industry -- have had a close and sometimes tense relationship for more than a decade.
Glasenberg hand-picked Davis to run Xstrata 11 years ago. Xstrata floated in 2002, after buying up key Glencore coal assets, leaving the trader with a 34 percent stake.
They clearly have a history together, as do Xstrata and Glencore, and I would expect nothing less than that they try to drive the best bargain for their shareholders, said analyst Jeff Largey at investment bank Macquarie in London.
One key element of Glencore's move on Xstrata -- which is being billed as a merger of equals -- is who gets to run the enlarged trader and miner.
The new company will get the bulk of its revenue from mining, leaving Davis as the obvious choice for the top job, while others point out that Glasenberg, who has said he does not plan to sell shares, is unlikely to step aside.
This has left some skeptical about whether the two brash characters would be able to work together in a combined company.
I don't think both will stay in a fully merged entity. Both have made so much money and I would not be surprised if one of them goes, said a senior investment banker familiar with the mining sector. Mick is more likely to be the one that moves.
Glasenberg is a billionaire, owning 15.8 percent of his company, while Davis regularly heads UK executive pay lists with his multi-million dollar earnings.
It's hard to say how it would actually shake out, but both of those gentlemen bring certain skillsets to the table, Macquarie's Largey said. If I was a shareholder in a combined entity I would like to think that they're both involved for at least a certain period of time.
Xstrata Chairman John Bond is expected to play a key role in negotiations and could be brought to chair the new group. Glencore's chairman, Simon Murray, has had a troubled nine months and would not be expected to remain, some analysts say.
MUCH IN COMMON
Glasenberg and Davis have much in common.
Both are in their mid-50s, come from mineral-rich South Africa and have powerful personalities.
And both are driven by deals.
Davis, however, is nicknamed Big Mick for his beefy frame and six-feet two-inch height. Glasenberg by contrast is medium height and wiry.
The fact that Davis was hired by Glasenberg has colored their relationship, said one source who knows the Glencore CEO.
There's a sense at Glencore that Mick wouldn't be where is today without Ivan, who chose him ... He owes it all to Ivan, the source said. At the same time, lots of people at Xstrata felt they were bullied by Glencore.
Industry sources and analysts say the two are committed professionals and would not allow any personal tensions to obstruct a deal that would benefit shareholders.
On the other hand, both are well known to drive a hard bargain and will not easily give in.
The relationship became fraught during the 2009 downturn when a debt-heavy Xstrata launched a rights issue, finding Glencore lacking the cash to take up its portion. Instead it agreed to contribute its prized Columbian coal operations.
Negotiations were tough and Davis ended up forcing Glasenberg to sharply lower his valuation for the Prodeco coal assets he contributed.
Both men, known for 70-hour work weeks and heavy travel schedules, showed ambition in their early professional lives after training as accountants in their homeland.
Glasenberg, known for both his fiery temper and his charm, joined Glencore as a coal trader in South Africa in 1983 and climbed via jobs in Australia, Hong Kong and Beijing before becoming chief executive in 2002.
Davis became finance director of South African utility Eskom at 29 but quit when he was overlooked for the CEO post. He was an executive for Billiton before it merged with BHP.
Glasenberg is a former South Africa and Israel champion race walker and insists on a daily run or swim to keep fit. Davis is a cricket fan, likely to slip references to the sport into any speech.
(Additional reporting by Victoria Howley and Clara Ferreira-Marques; Editing by David Holmes)