diff --git a/tests/include/TransientRegression.h b/tests/include/TransientRegression.h
index 87ab262e39..b369d249fc 100644
--- a/tests/include/TransientRegression.h
+++ b/tests/include/TransientRegression.h
@@ -29,6 +29,25 @@
 
 namespace neml2
 {
+
+struct AutoDefaultDtypeMode
+{
+  static std::mutex default_dtype_mutex;
+
+  AutoDefaultDtypeMode(c10::ScalarType default_dtype)
+    : prev_default_dtype(torch::typeMetaToScalarType(torch::get_default_dtype()))
+  {
+    default_dtype_mutex.lock();
+    torch::set_default_dtype(torch::scalarTypeToTypeMeta(default_dtype));
+  }
+  ~AutoDefaultDtypeMode()
+  {
+    default_dtype_mutex.unlock();
+    torch::set_default_dtype(torch::scalarTypeToTypeMeta(prev_default_dtype));
+  }
+  c10::ScalarType prev_default_dtype;
+};
+
 class TransientDriver;
 
 class TransientRegression : public Driver
diff --git a/tests/src/TransientRegression.cxx b/tests/src/TransientRegression.cxx
index 35c9537007..a9f62074bb 100644
--- a/tests/src/TransientRegression.cxx
+++ b/tests/src/TransientRegression.cxx
@@ -30,6 +30,8 @@ namespace fs = std::filesystem;
 
 namespace neml2
 {
+std::mutex AutoDefaultDtypeMode::default_dtype_mutex;
+
 register_NEML2_object(TransientRegression);
 
 OptionSet
@@ -56,6 +58,9 @@ TransientRegression::TransientRegression(const OptionSet & options)
 bool
 TransientRegression::run()
 {
+  // Paranoid guard
+  AutoDefaultDtypeMode dtype_mode(torch::kFloat64);
+
   _driver.run();
 
   // Verify the result