Gartmore's top European fund manager Roger Guy is to leave the firm, the company has announced – sending the share price tumbling.
The decision comes after Guy's co-manager Guillaume Rambourg resigned over an FSA investigation into his dealings.
The news wiped 15 per cent off the company's share price after the FTSE opened.
Meanwhile chief executive Jeffrey Meyer said the process was designed to rebuild the troubled company as well as kickstart discussions with potential buyers.
He said the company was "beginning to have discussions with other firms ... to see whether a business combination is in the best interest of our clients and our shareholders."
Meyer added the firm has not yet had material discussions with potential buyers.
"This is very much the beginning of the process for us," he said.
Gartmore, which also announced a £10m cost-cutting programme, added in a statement: “He (Roger Guy) has informed the Board that he wishes to retire from day-to-day fund management. Consequently,the Company has put in place a process to ensure an orderly handover of Roger's responsibilities and will combine the European Large Cap and All-Cap teams into a single European Equities Team."
John Bennett will take over his duties the firm after a handover period the firm said.