Citigroup CEO Michael Corbat shook up his senior management team this week.

Citigroup Inc. (C - Get Report) said investment-banking chief Ray McGuire will shift to a different role as part of a reorganization that aims to more seamlessly integrate the company's stock- and bond-underwriting businesses.

McGuire, who has led the investment-banking division for 13 years, will now focus on "managing senior global client relationships" and will "work strategically with our senior leaders with respect to critical decisions affecting clients," Citigroup President Jamie Forese wrote Thursday in an internal memo provided by a company spokeswoman. His title will be "Vice Chairman of Citigroup," a designation held by only one other executive at the bank, Steve Volk, who also serves as a liaison to major clients, according to the spokeswoman. 

New York-based Citigroup will combine its corporate and investment-banking group with its capital-markets origination business to create a new Banking, Capital Markets and Advisory division, or BCMA, according to the memo. Tyler Dickson, who oversees underwriting, and Manolo Falco, head of investment banking for Europe, will become global co-heads of the new division, reporting to Forese. McGuire will have the additional title of "Chairman of BCMA" and also will report to Forese. 

The changes come just days after CEO Michael Corbat announced that CFO John Gerspach would retire in March 2019. Bill Mills, Citigroup's regional CEO for North America, also will retire, and Jim Cowles, who oversees the company's operations in Europe, the Middle East and Africa, is leaving to start a non-profit organization.

Corbat promoted Mark Mason, a 17-year Citigroup veteran who has served as CFO of the Institutional Clients Group since 2014, to take over for Gerspach as CFO.

Citigroup shares fell 1.3% to $70.26 in trading on the New York Stock Exchange as of about noon on Thursday.