diff --git a/src/PhpseclibV3/StubSftpConnectionProvider.php b/src/PhpseclibV3/StubSftpConnectionProvider.php
index 2dc5258ef..0e673a7ee 100644
--- a/src/PhpseclibV3/StubSftpConnectionProvider.php
+++ b/src/PhpseclibV3/StubSftpConnectionProvider.php
@@ -25,6 +25,7 @@ public function disconnect(): void
     {
         if ($this->connection) {
             $this->connection->disconnect();
+            $this->connection = null;
         }
     }