diff --git a/wp-admin/includes/ajax-actions.php b/wp-admin/includes/ajax-actions.php
index 43f59b66ec..5985e3561a 100644
--- a/wp-admin/includes/ajax-actions.php
+++ b/wp-admin/includes/ajax-actions.php
@@ -3027,6 +3027,15 @@ function wp_ajax_parse_embed() {
 	$parsed = false;
 	$wp_embed->return_false_on_fail = true;
 
+	if ( 0 === $post_id ) {
+		/*
+		 * Refresh oEmbeds cached outside of posts that are past their TTL.
+		 * Posts are excluded because they have separate logic for refreshing
+		 * their post meta caches. See WP_Embed::cache_oembed().
+		 */
+		$wp_embed->usecache = false;
+	}
+
 	if ( is_ssl() && 0 === strpos( $url, 'http://' ) ) {
 		// Admin is ssl and the user pasted non-ssl URL.
 		// Check if the provider supports ssl embeds and use that for the preview.
diff --git a/wp-includes/class-wp-embed.php b/wp-includes/class-wp-embed.php
index c40ae2db59..4674caeb9f 100644
--- a/wp-includes/class-wp-embed.php
+++ b/wp-includes/class-wp-embed.php
@@ -284,12 +284,34 @@ class WP_Embed {
 				kses_remove_filters();
 			}
 
-			wp_insert_post( wp_slash( array(
-				'post_name'    => $key_suffix,
-				'post_content' => $html ? $html : '{{unknown}}',
-				'post_status'  => 'publish',
-				'post_type'    => 'oembed_cache',
-			) ) );
+			$insert_post_args = array(
+				'post_name' => $key_suffix,
+				'post_status' => 'publish',
+				'post_type' => 'oembed_cache',
+			);
+
+			if ( $html ) {
+				if ( $cached_post_id ) {
+					wp_update_post( wp_slash( array(
+						'ID' => $cached_post_id,
+						'post_content' => $html,
+					) ) );
+				} else {
+					wp_insert_post( wp_slash( array_merge(
+						$insert_post_args,
+						array(
+							'post_content' => $html,
+						)
+					) ) );
+				}
+			} elseif ( ! $cache ) {
+				wp_insert_post( wp_slash( array_merge(
+					$insert_post_args,
+					array(
+						'post_content' => '{{unknown}}',
+					)
+				) ) );
+			}
 
 			if ( $has_kses ) {
 				kses_init_filters();
diff --git a/wp-includes/version.php b/wp-includes/version.php
index e9a0df0663..74712b4389 100644
--- a/wp-includes/version.php
+++ b/wp-includes/version.php
@@ -4,7 +4,7 @@
  *
  * @global string $wp_version
  */
-$wp_version = '4.9-beta3-42008';
+$wp_version = '4.9-beta3-42009';
 
 /**
  * Holds the WordPress DB revision, increments when changes are made to the WordPress DB schema.