diff --git a/src/proto_alpha/lib_protocol/script_interpreter_defs.ml b/src/proto_alpha/lib_protocol/script_interpreter_defs.ml
index f63fcd930472f90d12e562ebf7eb4cf59764e312..9b2452fa0e99838e72b1924cdd4d78fa074dbaaf 100644
--- a/src/proto_alpha/lib_protocol/script_interpreter_defs.ml
+++ b/src/proto_alpha/lib_protocol/script_interpreter_defs.ml
@@ -582,7 +582,7 @@ let make_transaction_to_sc_rollup ctxt ~destination ~amount ~entrypoint
     error_unless (Entrypoint.is_default entrypoint) Rollup_invalid_entrypoint
   in
   let+ unparsed_parameters, ctxt =
-    unparse_data ctxt Optimized parameters_ty parameters
+    unparse_data ctxt Optimized_legacy parameters_ty parameters
   in
   ( Transaction_to_sc_rollup
       {destination; entrypoint; parameters_ty; parameters; unparsed_parameters},