diff --git a/core/lib/Drupal/Core/Entity/Controller/EntityViewController.php b/core/lib/Drupal/Core/Entity/Controller/EntityViewController.php
index 850d04b..672eed7 100644
--- a/core/lib/Drupal/Core/Entity/Controller/EntityViewController.php
+++ b/core/lib/Drupal/Core/Entity/Controller/EntityViewController.php
@@ -46,8 +46,10 @@ public static function create(ContainerInterface $container) {
   /**
    * Provides a page to render a single entity.
    *
-   * @param \Drupal\Core\Entity\EntityInterface $entity
-   *   The Entity to be rendered.
+   * @param \Drupal\Core\Entity\EntityInterface $_entity
+   *   The Entity to be rendered. Note this variable is named $_entity rather
+   *   than $entity to prevent collisions with other named placeholders in the
+   *   route.
    * @param string $view_mode
    *   The view mode that should be used to display the entity.
    * @param string $langcode
@@ -57,10 +59,10 @@ public static function create(ContainerInterface $container) {
    * @return array
    *   A render array as expected by drupal_render().
    */
-  public function view(EntityInterface $entity, $view_mode, $langcode = NULL) {
+  public function view(EntityInterface $_entity, $view_mode, $langcode = NULL) {
     return $this->entityManager
-      ->getRenderController($entity->entityType())
-      ->view($entity, $view_mode, $langcode);
+      ->getRenderController($_entity->entityType())
+      ->view($_entity, $view_mode, $langcode);
   }
 
 }
diff --git a/core/lib/Drupal/Core/Entity/Enhancer/EntityRouteEnhancer.php b/core/lib/Drupal/Core/Entity/Enhancer/EntityRouteEnhancer.php
index 66534a3..9bc8ee4 100644
--- a/core/lib/Drupal/Core/Entity/Enhancer/EntityRouteEnhancer.php
+++ b/core/lib/Drupal/Core/Entity/Enhancer/EntityRouteEnhancer.php
@@ -54,7 +54,7 @@ public function enhance(array $defaults, Request $request) {
         list($entity_type, $view_mode) = explode('.', $defaults['_entity_view']);
         // Set by reference so that we get the upcast value.
         if (!empty($defaults[$entity_type])) {
-          $defaults['entity'] = &$defaults[$entity_type];
+          $defaults['_entity'] = &$defaults[$entity_type];
         }
         else {
           // The entity is not keyed by its entity_type. Attempt to find it
@@ -62,12 +62,27 @@ public function enhance(array $defaults, Request $request) {
           $route = $defaults[RouteObjectInterface::ROUTE_OBJECT];
           if ($route && is_object($route)) {
             $options = $route->getOptions();
-            if (isset($options['converters'])) {
-              $flipped = array_flip($options['converters']);
-              if (isset($flipped[$entity_type]) && !empty($defaults[$flipped[$entity_type]])) {
-                $defaults['entity'] = &$defaults[$flipped[$entity_type]];
+            if (isset($options['parameters'])) {
+              foreach ($options['parameters'] as $name => $details) {
+                if (!empty($details['type'])) {
+                  $type = $details['type'];
+                  // Type is of the form entity:{entity_type}.
+                  $parameter_entity_type = substr($type, strlen('entity:'));
+                  if ($entity_type == $parameter_entity_type) {
+                    // We have the matching entity type. Set the '_entity' key
+                    // to point to this named placeholder. The entity in this
+                    // position is the one being rendered.
+                    $defaults['_entity'] = &$defaults[$name];
+                  }
+                }
               }
             }
+            else {
+              throw new \RuntimeException(sprintf('Failed to find entity of type %s in route named %s', $entity_type, $defaults[RouteObjectInterface::ROUTE_NAME]));
+            }
+          }
+          else {
+            throw new \RuntimeException(sprintf('Failed to find entity of type %s in route named %s', $entity_type, $defaults[RouteObjectInterface::ROUTE_NAME]));
           }
         }
         $defaults['view_mode'] = $view_mode;
diff --git a/core/modules/system/tests/modules/entity_test/entity_test.routing.yml b/core/modules/system/tests/modules/entity_test/entity_test.routing.yml
index 6cf2319..08b18fa 100644
--- a/core/modules/system/tests/modules/entity_test/entity_test.routing.yml
+++ b/core/modules/system/tests/modules/entity_test/entity_test.routing.yml
@@ -8,8 +8,9 @@ entity_test_render:
 entity_test_render_options:
   pattern: '/entity-test-render-converter/{foo}'
   options:
-    converters:
-      foo: 'entity_test_render'
+    parameters:
+      foo:
+        type: 'entity:entity_test_render'
   defaults:
     _entity_view: 'entity_test_render.full'
   requirements:
diff --git a/core/tests/Drupal/Tests/Core/Entity/Enhancer/EntityRouteEnhancerTest.php b/core/tests/Drupal/Tests/Core/Entity/Enhancer/EntityRouteEnhancerTest.php
index f6da78d..00dd172 100644
--- a/core/tests/Drupal/Tests/Core/Entity/Enhancer/EntityRouteEnhancerTest.php
+++ b/core/tests/Drupal/Tests/Core/Entity/Enhancer/EntityRouteEnhancerTest.php
@@ -71,7 +71,7 @@ public function testEnhancer() {
     $defaults = $route_enhancer->enhance($defaults, $request);
     $this->assertEquals('controller.page:content', $defaults['_controller']);
     $this->assertEquals('\Drupal\Core\Entity\Controller\EntityViewController::view', $defaults['_content'], 'The entity view controller was not set.');
-    $this->assertEquals($defaults['entity'], 'Mock entity');
+    $this->assertEquals($defaults['_entity'], 'Mock entity');
     $this->assertEquals($defaults['view_mode'], 'default');
     $this->assertFalse(isset($defaults['_entity_view']));
 
@@ -81,7 +81,7 @@ public function testEnhancer() {
     $defaults['_entity_view'] = 'entity_test.default';
     $defaults['foo'] = 'Mock entity';
     // Add a converter.
-    $options['converters']['foo'] = 'entity_test';
+    $options['parameters']['foo'] = array('type' => 'entity:entity_test');
     // Set the route.
     $route = $this->getMockBuilder('Symfony\Component\Routing\Route')
       ->disableOriginalConstructor()
@@ -95,7 +95,7 @@ public function testEnhancer() {
     $defaults = $route_enhancer->enhance($defaults, $request);
     $this->assertEquals('controller.page:content', $defaults['_controller']);
     $this->assertEquals('\Drupal\Core\Entity\Controller\EntityViewController::view', $defaults['_content'], 'The entity view controller was not set.');
-    $this->assertEquals($defaults['entity'], 'Mock entity');
+    $this->assertEquals($defaults['_entity'], 'Mock entity');
     $this->assertEquals($defaults['view_mode'], 'default');
     $this->assertFalse(isset($defaults['_entity_view']));
   }