diff --git a/modules/articoli/actions.php b/modules/articoli/actions.php
index dec37d893..45bcb947c 100644
--- a/modules/articoli/actions.php
+++ b/modules/articoli/actions.php
@@ -151,7 +151,7 @@ switch (post('op')) {
         preg_match("/(.*?)([\d]*$)/", $serial__end, $m);
         $serial_end = intval($m[2]);
         $n_serial = abs($serial_end - $serial_start) + 1;
-        $serial_prefix = str_replace($serial_end, '', $serial__end);
+        $serial_prefix = rtrim($serial__end,$serial_end);
         $serial_pad_length = strlen($serial__end) - strlen($serial_prefix);
 
         // Altro