diff --git a/wp-includes/ms-settings.php b/wp-includes/ms-settings.php
index 43724621a9..9022313e5d 100644
--- a/wp-includes/ms-settings.php
+++ b/wp-includes/ms-settings.php
@@ -59,9 +59,11 @@ if ( !isset( $current_site ) || !isset( $current_blog ) ) {
 			if ( $current_blog )
 				wp_cache_set( 'current_blog_' . $domain, $current_blog, 'site-options' );
 		}
-		if ( $current_blog && $current_blog->site_id != $current_site->id )
+		if ( $current_blog && $current_blog->site_id != $current_site->id ) {
 			$current_site = $wpdb->get_row( $wpdb->prepare( "SELECT * FROM $wpdb->site WHERE id = %d", $current_blog->site_id ) );
-		else
+			if ( ! isset( $current_site->blog_id ) )
+				$current_site->blog_id = $wpdb->get_var( $wpdb->prepare( "SELECT blog_id FROM $wpdb->blogs WHERE domain = %s AND path = %s", $current_site->domain, $current_site->path ) );
+		} else
 			$blogname = substr( $domain, 0, strpos( $domain, '.' ) );
 	} else {
 		$blogname = htmlspecialchars( substr( $_SERVER[ 'REQUEST_URI' ], strlen( $path ) ) );