According to the Project Management Body of Knowledge (PMBOK) Guide, when a stakeholder requests a change, especially when the project is nearing completion, the project manager should first raise a change request to the Change Control Board (CCB). The CCB is responsible for reviewing and approving or rejecting change requests. Informing the project sponsor about the change is also important as they need to be aware of potential impacts on the project's objectives and deliverables. This process ensures that changes are managed in a controlled manner, minimizing the risk of scope creep and maintaining the integrity of the project management plan. References: Project Management Professional (PMP) Reference Materials, PMBOK Guide, Chapter 4: Integration Management.