A mixer assembly for a vehicle exhaust system includes a mixer shell defining an internal cavity, wherein the mixer shell includes an upstream end configured to receive exhaust gases and downstream end. A reactor is positioned within the internal cavity and has a reactor inlet configured to receive injected fluid and a reactor outlet that directs a mixture of exhaust gas and injected fluid into the internal cavity. A flow diverter is associated with the reactor to direct exhaust gas bypassing the reactor to mix with the mixture exiting the reactor outlet prior to exiting the downstream end of the mixer.