As if Citigroup ( C ) didn't have enough of a mess from its parade of writedowns, the bank must now deal with the fallout from blowups at a series of hedge funds. Some of its high-net-worth clients, whose losses in the funds approach $2 billion, are threatening to move their money to rivals. That's prompting some of Citi's top brokers to consider leaving the bank as well. Citigroup is in damage-control mode, scrambling to stave off the exodus. The bank recently pumped $661 million into six troubled hedge funds and devised a restructuring plan that would allow investors potentially to recoup some of their money. The company is also arranging weekly conference calls with its sales force. "I don't want any of you to think that we have underestimated the impact of this on you or your clients," Sallie L. Krawcheck, chief of Citi's Global Wealth Management, told brokers in a call on Apr. 2. "This is the most important issue we have been dealing with [in the group]."