diff --git a/src/wp-includes/wp-db.php b/src/wp-includes/wp-db.php
index 6a8893ad7f..a30afa989d 100644
--- a/src/wp-includes/wp-db.php
+++ b/src/wp-includes/wp-db.php
@@ -3116,6 +3116,8 @@ class wpdb {
 
 		if ( $closed ) {
 			$this->dbh = null;
+			$this->ready = false;
+			$this->has_connected = false;
 		}
 
 		return $closed;
diff --git a/tests/phpunit/tests/db.php b/tests/phpunit/tests/db.php
index 583dba1d22..f49a3e07b6 100644
--- a/tests/phpunit/tests/db.php
+++ b/tests/phpunit/tests/db.php
@@ -946,6 +946,9 @@ class Tests_DB extends WP_UnitTestCase {
 		$this->assertTrue( $wpdb->close() );
 		$this->assertFalse( $wpdb->close() );
 
+		$this->assertFalse( $wpdb->ready );
+		$this->assertFalse( $wpdb->has_connected );
+
 		$wpdb->check_connection();
 
 		$this->assertTrue( $wpdb->close() );