diff --git a/plugins/psgi/psgi_loader.c b/plugins/psgi/psgi_loader.c
index dbb137f0..09f75798 100644
--- a/plugins/psgi/psgi_loader.c
+++ b/plugins/psgi/psgi_loader.c
@@ -11,8 +11,8 @@ XS(XS_input_seek) {
         dXSARGS;
 	struct wsgi_request *wsgi_req = current_wsgi_req();
 
-        psgi_check_args(1);
-	uwsgi_request_body_seek(wsgi_req, SvIV(ST(0)));
+        psgi_check_args(2);
+	uwsgi_request_body_seek(wsgi_req, SvIV(ST(1)));
 
         XSRETURN(0);
 }