diff --git a/roofit/histfactory/src/HistoToWorkspaceFactoryFast.cxx b/roofit/histfactory/src/HistoToWorkspaceFactoryFast.cxx
index 1a2fd3a311711..f5d9a473ffcf5 100644
--- a/roofit/histfactory/src/HistoToWorkspaceFactoryFast.cxx
+++ b/roofit/histfactory/src/HistoToWorkspaceFactoryFast.cxx
@@ -797,7 +797,6 @@ RooArgList HistoToWorkspaceFactoryFast::createObservables(const TH1 *hist, RooWo
     auto protoOwner = std::make_unique<RooWorkspace>(channel_name.c_str(), (channel_name+" workspace").c_str());
     RooWorkspace &proto = *protoOwner;
     auto proto_config = make_unique<ModelConfig>("ModelConfig", &proto);
-    proto_config->SetWorkspace(proto);
 
     // preprocess functions
     for(auto const& func : fPreprocessFunctions){