diff --git a/core/modules/system/system.admin.inc b/core/modules/system/system.admin.inc
index d344d37..6e5b451 100644
--- a/core/modules/system/system.admin.inc
+++ b/core/modules/system/system.admin.inc
@@ -305,33 +305,7 @@ function system_theme_enable() {
   throw new AccessDeniedHttpException();
 }
 
-/**
- * Menu callback; Disables a theme.
- */
-function system_theme_disable() {
-  if (isset($_REQUEST['theme']) && isset($_REQUEST['token']) && drupal_valid_token($_REQUEST['token'], 'system-theme-operation-link')) {
-    $theme = $_REQUEST['theme'];
-    // Get current list of themes.
-    $themes = list_themes();
 
-    // Check if the specified theme is one recognized by the system.
-    if (!empty($themes[$theme])) {
-      // Do not disable the default or admin theme.
-      if ($theme === config('system.theme')->get('default') || $theme === config('system.theme')->get('admin')) {
-        drupal_set_message(t('%theme is the default theme and cannot be disabled.', array('%theme' => $themes[$theme]->info['name'])), 'error');
-      }
-      else {
-        theme_disable(array($theme));
-        drupal_set_message(t('The %theme theme has been disabled.', array('%theme' => $themes[$theme]->info['name'])));
-      }
-    }
-    else {
-      drupal_set_message(t('The %theme theme was not found.', array('%theme' => $theme)), 'error');
-    }
-    drupal_goto('admin/appearance');
-  }
-  throw new AccessDeniedHttpException();
-}
 
 /**
  * Menu callback; Set the default theme.
diff --git a/core/modules/system/system.module b/core/modules/system/system.module
index 4d2f61e..6c50bdb 100644
--- a/core/modules/system/system.module
+++ b/core/modules/system/system.module
@@ -711,10 +711,8 @@ function system_menu() {
   );
   $items['admin/appearance/disable'] = array(
     'title' => 'Disable theme',
-    'page callback' => 'system_theme_disable',
-    'access arguments' => array('administer themes'),
+    'route_name' => 'system_theme_disable',
     'type' => MENU_CALLBACK,
-    'file' => 'system.admin.inc',
   );
   $items['admin/appearance/default'] = array(
     'title' => 'Set default theme',
diff --git a/core/modules/system/system.routing.yml b/core/modules/system/system.routing.yml
index b285844..2d47922 100644
--- a/core/modules/system/system.routing.yml
+++ b/core/modules/system/system.routing.yml
@@ -73,3 +73,11 @@ system_site_maintenance_mode:
     _form: 'Drupal\system\Form\SiteMaintenanceModeForm'
   requirements:
     _permission: 'administer site configuration'
+
+system_theme_disable:
+  pattern: '/admin/appearance/disable'
+  defaults:
+    _controller: 'Drupal\system\Controller\ThemeController::disable'
+  requirements:
+    _permission: 'administer themes'
+