Index: src/wp-includes/general-template.php
===================================================================
--- src/wp-includes/general-template.php	(revision 41327)
+++ src/wp-includes/general-template.php	(working copy)
@@ -1157,12 +1157,23 @@
 		$title = post_type_archive_title( '', false );
 	}
 
-	// If there's a month
+	// If there's a date
 	if ( is_archive() && ! empty( $m ) ) {
-		$my_year  = substr( $m, 0, 4 );
-		$my_month = $wp_locale->get_month( substr( $m, 4, 2 ) );
-		$my_day   = intval( substr( $m, 6, 2 ) );
-		$title    = $my_year . ( $my_month ? $t_sep . $my_month : '' ) . ( $my_day ? $t_sep . $my_day : '' );
+		// First add the year.
+		$date_parts = array( substr( $m, 0, 4 ) );
+
+		// is_time, is_day and is_month are mutually exclusive thus all need to be checked.
+		if ( is_time() || is_day() || is_month() ) {
+			// Then add the month.
+			$date_parts[] = $wp_locale->get_month( substr( $m, 4, 2 ) );
+		}
+
+		if ( is_time() || is_day() ) {
+			// Then add the day.
+			$date_parts[] = (int) substr( $m, 6, 2 );
+		}
+
+		$title = implode( $t_sep, $date_parts );
 	}
 
 	// If there's a year