Just as Merrill Lynch had shed its reputation as a hornets' nest of infighting, it has reverted to type with the exit of fixed income poster boy Osman Semerci that will have far-reaching consequences for the Wall street firm over the coming weeks and months.

The departure of 39-year old Semerci says two things about Merrill Lynch. Firstly, its third quarter results are going to be ugly, with write-downs of around $1.5bn (€1bn) in Semerci's global fixed income, commodities and currencies division. Secondly, after four years of relative calm, the starting pistol has been fired in the race to succeed Stan O'Neal as chairman and chief executive.