A retaining seal assembly for use in a gas turbine engine is provided. The retaining seal assembly comprises an outer retaining ring coupled to an aft end of a gas turbine engine combustor. A turbine nozzle is coupled to the outer retaining ring and comprises an outer band. The outer band comprises a leading edge and an opposing trailing edge that defines a slot. A retention seal comprises a first end positioned within the slot, a generally opposing second end that contacts the outer retaining ring, and a body extending between the first end and the second end. The body further comprises an insertion portion positioned within a passage formed in the outer band. The retention seal is fabricated from a resilient material and is configured to facilitate coupling the turbine nozzle to the outer retaining ring.