The invention relates to systems and methods for mitigating impact of vanadium in heavy fuel oil. Specifically, the invention provides a gas turbine engine for combusting a flow of heavy fuel oil (110) with vanadium contaminates therein. The gas turbine engine (10) may include a combustor (25) for combusting the flow of heavy fuel oil (110), an upstream magnesium mixing system (230) for mixing a flow of magnesium (240) with the flow of heavy fuel oil (110), a turbine, an air extraction system in communication with the turbine, and a downstream magnesium mixing system (410) for providing the flow of magnesium (240) to the air extraction system.