diff -u b/core/modules/media/src/MediaSourceBase.php b/core/modules/media/src/MediaSourceBase.php
--- b/core/modules/media/src/MediaSourceBase.php
+++ b/core/modules/media/src/MediaSourceBase.php
@@ -322,15 +322,15 @@
   /**
    * {@inheritdoc}
    */
-  public function prepareViewDisplay(MediaTypeInterface $type, $field_name, EntityViewDisplayInterface $display) {
-    $display->setComponent($field_name);
+  public function prepareViewDisplay(MediaTypeInterface $type, EntityViewDisplayInterface $display) {
+    $display->setComponent($this->getSourceFieldDefinition($type)->getName());
   }
 
   /**
    * {@inheritdoc}
    */
-  public function prepareFormDisplay(MediaTypeInterface $type, $field_name, EntityFormDisplayInterface $display) {
-    $display->setComponent($field_name);
+  public function prepareFormDisplay(MediaTypeInterface $type, EntityFormDisplayInterface $display) {
+    $display->setComponent($this->getSourceFieldDefinition($type)->getName());
   }
 
 }
diff -u b/core/modules/media/src/MediaSourceInterface.php b/core/modules/media/src/MediaSourceInterface.php
--- b/core/modules/media/src/MediaSourceInterface.php
+++ b/core/modules/media/src/MediaSourceInterface.php
@@ -143,42 +143,38 @@
 
   /**
-   * Prepares the source field in the view display.
+   * Prepares the media type fields for this source in the view display.
    *
    * This method should normally call
    * \Drupal\Core\Entity\Display\EntityDisplayInterface::setComponent() or
    * \Drupal\Core\Entity\Display\EntityDisplayInterface::removeComponent() to
-   * configure the source field in the view display.
+   * configure the media type fields in the view display.
    *
    * @param \Drupal\media\MediaTypeInterface $type
    *   The media type which is using this source.
-   * @param string $field_name
-   *   Field name of the source field.
    * @param \Drupal\Core\Entity\Display\EntityViewDisplayInterface $display
-   *   The display in which the field appears.
+   *   The display which should be prepared.
    *
    * @see \Drupal\Core\Entity\Display\EntityDisplayInterface::setComponent()
    * @see \Drupal\Core\Entity\Display\EntityDisplayInterface::removeComponent()
    */
-  public function prepareViewDisplay(MediaTypeInterface $type, $field_name, EntityViewDisplayInterface $display);
+  public function prepareViewDisplay(MediaTypeInterface $type, EntityViewDisplayInterface $display);
 
   /**
-   * Prepares the source field in the form display.
+   * Prepares the media type fields for this source in the form display.
    *
    * This method should normally call
    * \Drupal\Core\Entity\Display\EntityDisplayInterface::setComponent() or
    * \Drupal\Core\Entity\Display\EntityDisplayInterface::removeComponent() to
-   * configure the source field in the form display.
+   * configure the media type fields in the form display.
    *
    * @param \Drupal\media\MediaTypeInterface $type
    *   The media type which is using this source.
-   * @param string $field_name
-   *   Field name of the source field.
    * @param \Drupal\Core\Entity\Display\EntityFormDisplayInterface $display
-   *   The display in which the field appears.
+   *   The display which should be prepared.
    *
    * @see \Drupal\Core\Entity\Display\EntityDisplayInterface::setComponent()
    * @see \Drupal\Core\Entity\Display\EntityDisplayInterface::removeComponent()
    */
-  public function prepareFormDisplay(MediaTypeInterface $type, $field_name, EntityFormDisplayInterface $display);
+  public function prepareFormDisplay(MediaTypeInterface $type, EntityFormDisplayInterface $display);
 
 }
diff -u b/core/modules/media/src/MediaTypeForm.php b/core/modules/media/src/MediaTypeForm.php
--- b/core/modules/media/src/MediaTypeForm.php
+++ b/core/modules/media/src/MediaTypeForm.php
@@ -4,7 +4,6 @@
 
 use Drupal\Core\Ajax\AjaxResponse;
 use Drupal\Core\Ajax\ReplaceCommand;
-use Drupal\Core\Entity\Display\EntityDisplayInterface;
 use Drupal\Core\Entity\EntityFieldManagerInterface;
 use Drupal\Core\Entity\EntityForm;
 use Drupal\Core\Field\BaseFieldDefinition;
@@ -328,19 +327,18 @@
 
       // Add the new field to the default form and view displays for this
       // media type.
-      $field_name = $source_field->getName();
       if ($source_field->isDisplayConfigurable('form')) {
         // @todo Replace entity_get_form_display() when #2367933 is done.
         // https://www.drupal.org/node/2872159.
         $display = entity_get_form_display('media', $media_type->id(), 'default');
-        $source->prepareFormDisplay($media_type, $field_name, $display);
+        $source->prepareFormDisplay($media_type, $display);
         $display->save();
       }
       if ($source_field->isDisplayConfigurable('view')) {
         // @todo Replace entity_get_display() when #2367933 is done.
         // https://www.drupal.org/node/2872159.
         $display = entity_get_display('media', $media_type->id(), 'default');
-        $source->prepareViewDisplay($media_type, $field_name, $display);
+        $source->prepareViewDisplay($media_type, $display);
         $display->save();
       }
     }
diff -u b/core/modules/media/tests/modules/media_test_source/src/Plugin/media/Source/TestDifferentDisplays.php b/core/modules/media/tests/modules/media_test_source/src/Plugin/media/Source/TestDifferentDisplays.php
--- b/core/modules/media/tests/modules/media_test_source/src/Plugin/media/Source/TestDifferentDisplays.php
+++ b/core/modules/media/tests/modules/media_test_source/src/Plugin/media/Source/TestDifferentDisplays.php
@@ -21,15 +21,19 @@
   /**
    * {@inheritdoc}
    */
-  public function prepareViewDisplay(MediaTypeInterface $type, $field_name, EntityViewDisplayInterface $display) {
-    $display->setComponent($field_name, ['type' => 'entity_reference_entity_id']);
+  public function prepareViewDisplay(MediaTypeInterface $type, EntityViewDisplayInterface $display) {
+    $display->setComponent($this->getSourceFieldDefinition($type)->getName(), [
+      'type' => 'entity_reference_entity_id',
+    ]);
   }
 
   /**
    * {@inheritdoc}
    */
-  public function prepareFormDisplay(MediaTypeInterface $type, $field_name, EntityFormDisplayInterface $display) {
-    $display->setComponent($field_name, ['type' => 'entity_reference_autocomplete_tags']);
+  public function prepareFormDisplay(MediaTypeInterface $type, EntityFormDisplayInterface $display) {
+    $display->setComponent($this->getSourceFieldDefinition($type)->getName(), [
+      'type' => 'entity_reference_autocomplete_tags',
+    ]);
   }
 
   /**
diff -u b/core/modules/media/tests/modules/media_test_source/src/Plugin/media/Source/TestWithHiddenSourceField.php b/core/modules/media/tests/modules/media_test_source/src/Plugin/media/Source/TestWithHiddenSourceField.php
--- b/core/modules/media/tests/modules/media_test_source/src/Plugin/media/Source/TestWithHiddenSourceField.php
+++ b/core/modules/media/tests/modules/media_test_source/src/Plugin/media/Source/TestWithHiddenSourceField.php
@@ -21,15 +21,15 @@
   /**
    * {@inheritdoc}
    */
-  public function prepareViewDisplay(MediaTypeInterface $type, $field_name, EntityViewDisplayInterface $display) {
-    $display->removeComponent($field_name);
+  public function prepareViewDisplay(MediaTypeInterface $type, EntityViewDisplayInterface $display) {
+    $display->removeComponent($this->getSourceFieldDefinition($type)->getName());
   }
 
   /**
    * {@inheritdoc}
    */
-  public function prepareFormDisplay(MediaTypeInterface $type, $field_name, EntityFormDisplayInterface $display) {
-    $display->removeComponent($field_name);
+  public function prepareFormDisplay(MediaTypeInterface $type, EntityFormDisplayInterface $display) {
+    $display->removeComponent($this->getSourceFieldDefinition($type)->getName());
   }
 
   /**