diff --git a/racket/collects/racket/contract/private/arr-i.rkt b/racket/collects/racket/contract/private/arr-i.rkt
index fdf4e7698b..aec73cf7ca 100644
--- a/racket/collects/racket/contract/private/arr-i.rkt
+++ b/racket/collects/racket/contract/private/arr-i.rkt
@@ -915,7 +915,7 @@ evaluted left-to-right.)
                   blame+neg-party
                   (apply arg-checker args)))))
             impersonator-prop:contracted ctc
-            impersonator-prop:blame blame))))))
+            impersonator-prop:blame (blame-add-missing-party blame neg-party)))))))
 
 (define-for-syntax (arg/res-to-indy-var indy-arg-vars ordered-args indy-res-vars ordered-ress var)
   (define (try vars ordered)
diff --git a/racket/collects/racket/contract/private/opters.rkt b/racket/collects/racket/contract/private/opters.rkt
index 849a67cbb1..54e5c750df 100644
--- a/racket/collects/racket/contract/private/opters.rkt
+++ b/racket/collects/racket/contract/private/opters.rkt
@@ -607,7 +607,8 @@
                         (null? b)))
                  (chaperone-procedure val exact-proc
                                       impersonator-prop:application-mark 
-                                      (cons opt->/c-cm-key cont-mark-value))
+                                      (cons opt->/c-cm-key cont-mark-value)
+                                      impersonator-prop:blame blame)
                  (handle-non-exact-procedure val dom-len blame exact-proc))))
        (append lifts-doms lifts-rngs)
        (append superlifts-doms superlifts-rngs)
@@ -678,7 +679,8 @@
                 (case-lambda
                   [(dom-arg ...)  (values next-dom ...)]
                   [args
-                   (bad-number-of-arguments blame val args dom-len)]))))
+                   (bad-number-of-arguments blame val args dom-len)])
+                impersonator-prop:blame blame)))
          (if all-anys?
              #`(if (procedure-arity-exactly/no-kwds val #,(length doms))
                    val