diff --git a/bin/pyenv-virtualenv-init b/bin/pyenv-virtualenv-init
index f521808..080f54b 100755
--- a/bin/pyenv-virtualenv-init
+++ b/bin/pyenv-virtualenv-init
@@ -151,7 +151,7 @@ EOS
     cat <<EOS
 typeset -g -a precmd_functions
 if [[ -z \$precmd_functions[(r)_pyenv_virtualenv_hook] ]]; then
-  precmd_functions+=_pyenv_virtualenv_hook;
+  precmd_functions=(_pyenv_virtualenv_hook \$precmd_functions);
 fi
 EOS
     ;;
diff --git a/test/init.bats b/test/init.bats
index ba6a30f..b280fdb 100644
--- a/test/init.bats
+++ b/test/init.bats
@@ -141,7 +141,7 @@ _pyenv_virtualenv_hook() {
 };
 typeset -g -a precmd_functions
 if [[ -z \$precmd_functions[(r)_pyenv_virtualenv_hook] ]]; then
-  precmd_functions+=_pyenv_virtualenv_hook;
+  precmd_functions=(_pyenv_virtualenv_hook \$precmd_functions);
 fi
 EOS
 }