diff --git a/plumbum/commands/processes.py b/plumbum/commands/processes.py
index a34d74c82..3ecc13e97 100644
--- a/plumbum/commands/processes.py
+++ b/plumbum/commands/processes.py
@@ -127,6 +127,8 @@ def __init__(self, argv, retcode, stdout, stderr, message=None, host=None):
         if isinstance(stdout, list):
             assert isinstance(stderr, list)
             self.all_output += self._format_lines(heapq.merge(stdout, stderr))
+            self.stdout = "\n".join(line for *_, line in stdout)
+            self.stderr = "\n".join(line for *_, line in stderr)
         else:
             if isinstance(stdout, bytes):
                 stdout = ascii(stdout)