It's a Mumbai bound train so they have attached dead diesel loco behind it where that dead D loco will haul from Wadi - Pune .But I have a feeling why it was BZA WAP4, usually this train hauled by RPM P7 upto GTL .Or they might have changed e loco twice from MAS - GTL RPM P7 and from GTL - Wadi BZA WAP4 trailing behind dead Diesel loco.