diff --git a/src/mca/pml/base/pml_base_sendreq.h b/src/mca/pml/base/pml_base_sendreq.h
index 1fdeb27d85..847e08a100 100644
--- a/src/mca/pml/base/pml_base_sendreq.h
+++ b/src/mca/pml/base/pml_base_sendreq.h
@@ -108,7 +108,7 @@ typedef struct mca_pml_base_send_request_t mca_pml_base_send_request_t;
                                        (request)->req_base.req_datatype,  \
                                        (request)->req_base.req_count,     \
                                        (request)->req_base.req_addr,      \
-                                       0, NULL );                         \
+                                       -1, NULL );                        \
          ompi_convertor_get_packed_size( &(request)->req_convertor,       \
                               (uint32_t*)&((request)->req_bytes_packed) );\
       } else {                                                            \