diff --git a/src/poetry/console/commands/self/self_command.py b/src/poetry/console/commands/self/self_command.py
index 37738f44b1d..0c1a4ec3f79 100644
--- a/src/poetry/console/commands/self/self_command.py
+++ b/src/poetry/console/commands/self/self_command.py
@@ -75,7 +75,7 @@ def generate_system_pyproject(self) -> None:
         content = Factory.create_pyproject_from_package(package=package)
 
         for key in preserved:
-            content[key] = preserved[key]
+            content["tool"]["poetry"][key] = preserved[key]  # type: ignore[index]
 
         self.system_pyproject.write_text(content.as_string(), encoding="utf-8")