From the outside, BlackRock's $13.5bn (€9.7bn) acquisition of Barclays's money-management unit looked like any other smoothly orchestrated deal. Behind the scenes, though, the announcement was preceded by a high-stakes, last-minute tussle with a major backer who failed to come through with what BlackRock expected.

On the evening of June 9, BlackRock chief executive Laurence D Fink was finalising the details of the deal to acquire Barclays's money-management unit, Barclays Global Investors. The acquisition would make BlackRock the world's largest money manager, overseeing $2.8 trillion in assets. And it would propel Fink, who long dwelled just below Wall Street's top rungs, to a perch above his peers.