diff --git a/lisp/gnus/gnus-search.el b/lisp/gnus/gnus-search.el
index 605d8a34e9..871163c38b 100644
--- a/lisp/gnus/gnus-search.el
+++ b/lisp/gnus/gnus-search.el
@@ -1396,17 +1396,22 @@ gnus-search-indexed-parse-output
                    (file-readable-p f-name)
 		   (null (file-directory-p f-name)))
           (setq group
-                (replace-regexp-in-string
-	         "[/\\]" "."
-	         (replace-regexp-in-string
-	          "/?\\(cur\\|new\\|tmp\\)?/\\'" ""
+                (delete
+                 ""
+                 (file-name-split
 	          (replace-regexp-in-string
-	           "\\`\\." ""
-	           (string-remove-prefix
+	           "\\`\\." "" ; Why do we do this?
+                   (string-remove-prefix
                     prefix (file-name-directory f-name))
-                   nil t)
-	          nil t)
-	         nil t))
+                   nil t)))
+                ;; Turn file name segments into Gnus group name.
+                group (mapconcat
+                       #'identity
+                       (if (member (car (last group))
+                                   '("new" "tmp" "cur"))
+                           (nbutlast group)
+                         group)
+                       "."))
           (setq article (file-name-nondirectory f-name)
                 article
                 ;; TODO: Provide a cleaner way of producing final
@@ -1434,6 +1439,14 @@ gnus-search-indexed-parse-output
 		 (string-to-number score))))
             artlist)))
 
+(cl-defmethod gnus-search-indexed-extract :around
+  ((_engine gnus-search-indexed))
+  (let ((ret (cl-call-next-method)))
+    ;; We run `expand-file-name' here in order to collapse multiple
+    ;; consecutive directory separators.
+    (cl-callf expand-file-name (car ret))
+    ret))
+
 (cl-defmethod gnus-search-indexed-extract ((_engine gnus-search-indexed))
   "Base implementation treats the whole line as a filename, and
 fudges a relevancy score of 100."