diff --git a/python/dune/codegen/loopy/symbolic.py b/python/dune/codegen/loopy/symbolic.py
index 799c7d6040e2e7d9e40c296d73c391aeb43cc6f3..c76fbb063b88b62732ac54bbce39f532ba96aa9a 100644
--- a/python/dune/codegen/loopy/symbolic.py
+++ b/python/dune/codegen/loopy/symbolic.py
@@ -122,6 +122,7 @@ lp.type_inference.TypeInferenceMapper.map_vectorized_sumfact_kernel = needs_reso
 
 # FusedMultiplyAdd node
 lp.symbolic.IdentityMapper.map_fused_multiply_add = identity_map_fused_multiply_add
+lp.symbolic.SubstitutionMapper.map_fused_multiply_add = identity_map_fused_multiply_add
 lp.symbolic.WalkMapper.map_fused_multiply_add = walk_map_fused_multiply_add
 lp.symbolic.StringifyMapper.map_fused_multiply_add = stringify_map_fused_multiply_add
 lp.symbolic.DependencyMapper.map_fused_multiply_add = dependency_map_fused_multiply_add