diff --git a/Doc/library/io.rst b/Doc/library/io.rst
index 9738c5c2ad2..0f1251687ae 100644
--- a/Doc/library/io.rst
+++ b/Doc/library/io.rst
@@ -719,15 +719,15 @@ than raw I/O does.
 .. class:: BufferedRandom(raw, buffer_size=DEFAULT_BUFFER_SIZE)
 
    A buffered interface to random access streams.  It inherits
-   :class:`BufferedReader` and :class:`BufferedWriter`, and further supports
-   :meth:`seek` and :meth:`tell` functionality.
+   :class:`BufferedReader` and :class:`BufferedWriter`.
 
    The constructor creates a reader and writer for a seekable raw stream, given
    in the first argument.  If the *buffer_size* is omitted it defaults to
    :data:`DEFAULT_BUFFER_SIZE`.
 
    :class:`BufferedRandom` is capable of anything :class:`BufferedReader` or
-   :class:`BufferedWriter` can do.
+   :class:`BufferedWriter` can do.  In addition, :meth:`seek` and :meth:`tell`
+   are guaranteed to be implemented.
 
 
 .. class:: BufferedRWPair(reader, writer, buffer_size=DEFAULT_BUFFER_SIZE)