diff --git a/guix/grafts.scm b/guix/grafts.scm
index f93da32981..48f4c212f7 100644
--- a/guix/grafts.scm
+++ b/guix/grafts.scm
@@ -1,5 +1,5 @@
 ;;; GNU Guix --- Functional package management for GNU
-;;; Copyright © 2014-2022 Ludovic Courtès <ludo@gnu.org>
+;;; Copyright © 2014-2023 Ludovic Courtès <ludo@gnu.org>
 ;;;
 ;;; This file is part of GNU Guix.
 ;;;
@@ -176,11 +176,8 @@ references."
                     (append-map (cut references/cached store <>) items))))
       (append-map (cut references/cached store <>) items)))
 
-  (let ((refs (references* (map (cut derivation->output-path drv <>)
-                                outputs)))
-        (self (match (derivation->output-paths drv)
-                (((names . items) ...)
-                 items))))
+  (let* ((self (map (cut derivation->output-path drv <>) outputs))
+         (refs (references* self)))
     (remove (cut member <> self) refs)))
 
 (define %graft-cache
@@ -207,7 +204,7 @@ references."
            (return result)))))))
 
 (define (reference-origins drv items)
-  "Return the derivation/output pairs among the inputs of DRV, recursively,
+  "Return the derivation/output pairs among DRV and its inputs, recursively,
 that produce ITEMS.  Elements of ITEMS not produced by a derivation (i.e.,
 it's a content-addressed \"source\"), or not produced by a dependency of DRV,
 have no corresponding element in the resulting list."
@@ -238,13 +235,10 @@ have no corresponding element in the resulting list."
              ((set-contains? visited drv)
               (loop rest items result visited))
              (else
-              (let* ((inputs
-                      (map derivation-input-derivation
-                           (derivation-inputs drv)))
-                     (result items
-                             (fold2 lookup-derivers
-                                    result items inputs)))
-                (loop (append rest inputs)
+              (let ((result items (lookup-derivers drv result items)))
+                (loop (append rest
+                              (map derivation-input-derivation
+                                   (derivation-inputs drv)))
                       items result
                       (set-insert drv visited)))))))))
 
@@ -258,16 +252,17 @@ GRAFTS to the dependencies of DRV.  Return the resulting list of grafts.
 
 This is a monadic procedure in %STATE-MONAD where the state is a vhash mapping
 derivations to the corresponding set of grafts."
-  (define (graft-origin? drv graft)
-    ;; Return true if DRV corresponds to the origin of GRAFT.
+  (define (graft-origin? drv output graft)
+    ;; Return true if DRV and OUTPUT correspond to the origin of GRAFT.
     (match graft
-      (($ <graft> (? derivation? origin) output)
-       (match (assoc-ref (derivation->output-paths drv) output)
-         ((? string? result)
-          (string=? result
-                    (derivation->output-path origin output)))
-         (_
-          #f)))
+      (($ <graft> (? derivation? origin) origin-output)
+       (and (string=? origin-output output)
+            (match (assoc-ref (derivation->output-paths drv) output)
+              ((? string? result)
+               (string=? result
+                         (derivation->output-path origin output)))
+              (_
+               #f))))
       (_
        #f)))
 
@@ -278,7 +273,7 @@ derivations to the corresponding set of grafts."
               ((drv . output)
                ;; If GRAFTS already contains a graft from DRV, do not
                ;; override it.
-               (if (find (cut graft-origin? drv <>) grafts)
+               (if (find (cut graft-origin? drv output <>) grafts)
                    (state-return grafts)
                    (cumulative-grafts store drv grafts
                                       #:outputs (list output)
diff --git a/tests/grafts.scm b/tests/grafts.scm
index 63dbb13830..24c4d24359 100644
--- a/tests/grafts.scm
+++ b/tests/grafts.scm
@@ -1,5 +1,5 @@
 ;;; GNU Guix --- Functional package management for GNU
-;;; Copyright © 2014-2019, 2022 Ludovic Courtès <ludo@gnu.org>
+;;; Copyright © 2014-2019, 2022-2023 Ludovic Courtès <ludo@gnu.org>
 ;;; Copyright © 2021 Mark H Weaver <mhw@netris.org>
 ;;;
 ;;; This file is part of GNU Guix.
@@ -268,6 +268,54 @@
                           (readlink (string-append out "/two")))
                 (file-exists? (string-append out "/one/replacement")))))))
 
+(test-assert "graft-derivation, multiple outputs need to be replaced"
+  ;; Build a reference graph like this:
+  ;;
+  ;;         ,- p2:out --.
+  ;;         v           v
+  ;;      p1:one <---- p1:two
+  ;;         |
+  ;;         `-> p0
+  ;;
+  ;; Graft p0r in lieu of p0, and make sure all the paths from the grafted p2
+  ;; lead to p0r.  See <https://issues.guix.gnu.org/66662>.
+  (let* ((p0  (build-expression->derivation
+               %store "p0" '(mkdir (assoc-ref %outputs "out"))))
+         (p0r (build-expression->derivation
+               %store "P0"
+               '(let ((out (assoc-ref %outputs "out")))
+                  (mkdir out)
+                  (call-with-output-file (string-append out "/replacement")
+                    (const #t)))))
+         (p1  (build-expression->derivation
+               %store "p1"
+               `(let ((one (assoc-ref %outputs "one"))
+                      (two (assoc-ref %outputs "two"))
+                      (p0  (assoc-ref %build-inputs "p0")))
+                  (mkdir one)
+                  (mkdir two)
+                  (symlink p0 (string-append one "/p0"))
+                  (symlink one (string-append two "/link")))
+               #:inputs `(("p0" ,p0))
+               #:outputs '("one" "two")))
+         (p2  (build-expression->derivation
+               %store "p2"
+               `(let ((out (assoc-ref %outputs "out")))
+                  (mkdir out) (chdir out)
+                  (symlink (assoc-ref %build-inputs "p1:one") "one")
+                  (symlink (assoc-ref %build-inputs "p1:two") "two"))
+               #:inputs `(("p1:one" ,p1 "one")
+                          ("p1:two" ,p1 "two"))))
+         (p0g (list (graft
+                      (origin p0)
+                      (replacement p0r))))
+         (p2d (graft-derivation %store p2 p0g)))
+
+    (build-derivations %store (list p2d))
+    (let ((out (derivation->output-path (pk 'p2d p2d))))
+      (equal? (stat (string-append out "/one/p0/replacement"))
+              (stat (string-append out "/two/link/p0/replacement"))))))
+
 (test-assert "graft-derivation with #:outputs"
   ;; Call 'graft-derivation' with a narrowed set of outputs passed as
   ;; #:outputs.