diff --git a/aiohttp/web.py b/aiohttp/web.py
index 210fe09e75d..cc86ff9230e 100644
--- a/aiohttp/web.py
+++ b/aiohttp/web.py
@@ -193,7 +193,7 @@ def __init__(self, *, logger=web_logger, loop=None,
 
         for factory in middlewares:
             assert asyncio.iscoroutinefunction(factory), factory
-        self._middlewares = tuple(middlewares)
+        self._middlewares = list(middlewares)
 
     @property
     def router(self):
diff --git a/docs/web_reference.rst b/docs/web_reference.rst
index e1ff207568f..94af32a70f6 100644
--- a/docs/web_reference.rst
+++ b/docs/web_reference.rst
@@ -840,7 +840,7 @@ arbitrary properties for later access from
 
                   By default the value is ``logging.getLogger("aiohttp.web")``
 
-   :param middlewares: sequence of middleware factories, see
+   :param middlewares: :class:`list` of middleware factories, see
                        :ref:`aiohttp-web-middlewares` for details.
 
                        .. versionadded:: 0.13