Pressure induced metallization has been observed at ~4 GPa in G-type antiferromagnet BaMn2As2 using temperature dependent resistivity measurements. RT XRD measurements suggest that the metallization is not associated with a structural change. It is proposed to investigate evolution of the magnetic ground state across this insulator to metal transition using high pressure neutron diffraction. Temperature dependent high pressure neutron diffraction will be able to identify the origin of the transitions observed in high pressure resistivity data and clarify whether these anomalies arise from structural or magnetic origins.