diff --git a/Doc/lib/libdoctest.tex b/Doc/lib/libdoctest.tex
index 0741aa0bfae..c9c601b1d39 100644
--- a/Doc/lib/libdoctest.tex
+++ b/Doc/lib/libdoctest.tex
@@ -364,6 +364,7 @@ can also be used in doctest directives (see below).
     contains digit \code{1} where actual output contains letter \code{l},
     a line is inserted with a caret marking the mismatching column
     positions.
+  \versionadded{2.4}
 \end{datadesc}
 
 A "doctest directive" is a trailing Python comment on a line of a doctest