Citigroup, which warned last week that quarterly earnings would tumble 60 percent because of the crisis in the credit markets, has announced a shakeup in its corporate suite.

Two executives are leaving the bank: Thomas Maheras, co-chief executive of investment banking who oversaw trading, and Randy Barker, a top fixed-income executive.

Vikram Pandit, 50, a former Morgan Stanley executive, will now head trading, investment banking, and alternative investments. Pandit joined Citigroup when the bank acquired his hedge fund for $800 million earlier this year.

The moves bolster Pandit's standing as the most likely successor to Charles Prince, Citigroup's chief executive. Yet another possible candidate remains. Michael Klein stays on as co-chief executive of investment banking.

The shakeup buys some time for Prince, who has been under pressure from investors to rev up growth at Citi and help its stock price, which has barely budged since he became C.E.O. in October 2003.

In an interview with the New York Times, Prince was optimistic he could lead the bank with his new team.

"My job is to try to assess the situation and constantly reassess the best people we have got," Prince told the Times. "We have gone through a review of people in this business, and this is my view of the best lineup. My job is to put the best players on the field."