diff --git a/python/qemu/qmp/legacy.py b/python/qemu/qmp/legacy.py
index 8b09ee7dbb..b1eb3f360f 100644
--- a/python/qemu/qmp/legacy.py
+++ b/python/qemu/qmp/legacy.py
@@ -150,12 +150,13 @@ def connect(self, negotiate: bool = True) -> Optional[QMPMessage]:
         :return: QMP greeting dict, or None if negotiate is false
         :raise ConnectError: on connection errors
         """
-        assert self._address is not None
+        addr_or_sock = self._address or self._sock
+        assert addr_or_sock is not None
         self._qmp.await_greeting = negotiate
         self._qmp.negotiate = negotiate
 
         self._sync(
-            self._qmp.connect(self._address)
+            self._qmp.connect(addr_or_sock)
         )
         return self._get_greeting()