diff --git a/system/CodeIgniter.php b/system/CodeIgniter.php
index ef965d0d8df5..4bde1c042b6d 100644
--- a/system/CodeIgniter.php
+++ b/system/CodeIgniter.php
@@ -451,7 +451,7 @@ protected function handleRequest(?RouteCollectionInterface $routes, Cache $cache
 
         $uri = $this->determinePath();
 
-        if ($this->enableFilters && $this->checkControllerNotFoundBeforeFilter()) {
+        if ($this->enableFilters) {
             // Start up the filters
             $filters = Services::filters();
 
@@ -1159,22 +1159,4 @@ protected function outputBufferingEnd(): string
 
         return $buffer;
     }
-
-    /**
-     * Check whether the controller is not found before the before filter.
-     */
-    protected function checkControllerNotFoundBeforeFilter(): bool
-    {
-        // Check whether the controller type is Closure.
-        if (is_object($this->controller) && (get_class($this->controller) === 'Closure')) {
-            return true;
-        }
-
-        // Try to autoload the class
-        if (! class_exists($this->controller, true) || $this->method[0] === '_') {
-            throw PageNotFoundException::forControllerNotFound($this->controller, $this->method);
-        }
-
-        return true;
-    }
 }
diff --git a/system/Router/AutoRouter.php b/system/Router/AutoRouter.php
index f7cd02a3d329..918653633037 100644
--- a/system/Router/AutoRouter.php
+++ b/system/Router/AutoRouter.php
@@ -174,6 +174,11 @@ public function getRoute(string $uri, string $httpVerb): array
             );
         }
 
+        // Check if the controller exists.
+        if (! class_exists($this->controller, true) || $this->method[0] === '_') {
+            throw PageNotFoundException::forControllerNotFound($this->controller, $this->method);
+        }
+
         return [$this->directory, $this->controllerName(), $this->methodName(), $params];
     }
 
diff --git a/user_guide_src/source/changelogs/v4.4.2.rst b/user_guide_src/source/changelogs/v4.4.2.rst
index 19f2a4f1782c..9351a3791fc1 100644
--- a/user_guide_src/source/changelogs/v4.4.2.rst
+++ b/user_guide_src/source/changelogs/v4.4.2.rst
@@ -12,6 +12,8 @@ Release Date: Unreleased
 BREAKING
 ********
 
+- **AutoRouting Legacy:** Add a condition to check if the controller exists.
+
 Message Changes
 ***************