Eastern Bank has hired away Quincy Miller, who just last year was named Citizens Bank’s leader in Massachusetts, to be the second-in-command within the company.

Miller will succeed Robert Rivers as president when Rivers ascends to the positions of CEO and chairman on Jan. 1, 2017.

With Miller’s departure, Sargent is returning to the Massachusetts president position, in addition to continuing in the new lending role.

He has been CEO of Eastern for nine years, overseeing the acquisition of five banks with more than $3 billion in assets, the growth of Eastern’s insurance subsidiary, and the launch of an in-house technology incubator known as Eastern Labs.

Rivers is succeeding Holbrook as the leader of both the bank itself as well as the holding company, Eastern Bank Corp.