diff --git a/lisp/subr.el b/lisp/subr.el
index 036f414262a..d97598ab61f 100644
--- a/lisp/subr.el
+++ b/lisp/subr.el
@@ -7625,7 +7625,7 @@ as a list.")
                          (directory-file-name dir))))
             ;; This needs to match only the version strings that can be
             ;; generated by `package-version-join'.
-            (if (string-match "\\([^.].*?\\)-\\([0-9]+\\(?:[.][0-9]+\\|\\(?:pre\\|beta\\|alpha\\|snapshot\\)[0-9]+\\)*\\)\\'" subdir)
+            (if (string-match "\\([^.].*?\\)-\\([0-9]+\\(?:[.][0-9]+\\|\\(?:pre\\|beta\\|alpha\\|snapshot\\)[0-9]*\\)*\\)\\'" subdir)
                 (match-string 1 subdir) subdir))
           "-pkg.el"))