diff --git a/MaterialLib/SolidModels/MFront/MFront.cpp b/MaterialLib/SolidModels/MFront/MFront.cpp
index b43b7bd55f2b3e48fab0217971f5f0c724c40af2..a35af7cc27af5ee789b22b4a42c864c8e604d247 100644
--- a/MaterialLib/SolidModels/MFront/MFront.cpp
+++ b/MaterialLib/SolidModels/MFront/MFront.cpp
@@ -311,7 +311,7 @@ MFront<DisplacementDim>::integrateStress(
                 "before calling MFront::integrateStress.");
         }
 
-        behaviour_data.s1.external_state_variables[0] = std::get<double>(
+        behaviour_data.s0.external_state_variables[0] = std::get<double>(
             variable_array_prev[static_cast<int>(MPL::Variable::temperature)]);
     }