diff --git a/pkg/compiler/lib/src/ir/scope_visitor.dart b/pkg/compiler/lib/src/ir/scope_visitor.dart
index 0b2385bbead..9888c6abb10 100644
--- a/pkg/compiler/lib/src/ir/scope_visitor.dart
+++ b/pkg/compiler/lib/src/ir/scope_visitor.dart
@@ -403,6 +403,9 @@ class ScopeModelBuilder extends ir.VisitorDefault<EvaluationComplexity>
   @override
   EvaluationComplexity visitStructuralParameter(
       ir.StructuralParameter typeParameter) {
+    // Visit the default type to register any necessary type parameters that RTI
+    // might need if the associated function is used as a generic tear off.
+    visitNode(typeParameter.defaultType);
     return const EvaluationComplexity.constant();
   }
 
diff --git a/tests/web/regress/issue/54451_test.dart b/tests/web/regress/issue/54451_test.dart
new file mode 100644
index 00000000000..1cf9bb51a82
--- /dev/null
+++ b/tests/web/regress/issue/54451_test.dart
@@ -0,0 +1,25 @@
+// Copyright (c) 2023, the Dart project authors.  Please see the AUTHORS file
+// for details. All rights reserved. Use of this source code is governed by a
+// BSD-style license that can be found in the LICENSE file.
+
+// Tests that the bounds for structural parameters of a Function type are
+// visited and any type variables RTI might need are registered.
+
+class A<T> {
+  void foo1() {
+    void bar1<Z extends void Function<Y extends T>()>() {}
+    print(bar1.runtimeType); // Crashes compiler if A.T is not accessible.
+  }
+}
+
+extension<T> on T {
+  void foo2() {
+    void bar2<Z extends void Function<Y extends T>()>() {}
+    print(bar2.runtimeType); // Crashes compiler if T is not accessible.
+  }
+}
+
+void main() {
+  A<int>().foo1();
+  1.foo2();
+}