diff --git a/builtin/diff.c b/builtin/diff.c
index 4c0811d6fc..1a1149eed4 100644
--- a/builtin/diff.c
+++ b/builtin/diff.c
@@ -23,6 +23,11 @@
 static const char builtin_diff_usage[] =
 "git diff [<options>] [<commit> [<commit>]] [--] [<path>...]";
 
+static const char *blob_path(struct object_array_entry *entry)
+{
+	return entry->path ? entry->path : entry->name;
+}
+
 static void stuff_change(struct diff_options *opt,
 			 unsigned old_mode, unsigned new_mode,
 			 const struct object_id *old_oid,
@@ -110,7 +115,7 @@ static int builtin_diff_blobs(struct rev_info *revs,
 		     blob[0]->mode, blob[1]->mode,
 		     &blob[0]->item->oid, &blob[1]->item->oid,
 		     1, 1,
-		     blob[0]->name, blob[1]->name);
+		     blob_path(blob[0]), blob_path(blob[1]));
 	diffcore_std(&revs->diffopt);
 	diff_flush(&revs->diffopt);
 	return 0;
diff --git a/t/t4063-diff-blobs.sh b/t/t4063-diff-blobs.sh
index df9c35b2dd..80ce033ab6 100755
--- a/t/t4063-diff-blobs.sh
+++ b/t/t4063-diff-blobs.sh
@@ -55,7 +55,7 @@ test_expect_success 'diff by tree:path (run)' '
 test_expect_success 'index of tree:path diff' '
 	check_index $sha1_one $sha1_two
 '
-test_expect_failure 'tree:path diff uses filenames as paths' '
+test_expect_success 'tree:path diff uses filenames as paths' '
 	check_paths one two
 '
 test_expect_success 'tree:path diff shows mode change' '
@@ -68,7 +68,7 @@ test_expect_success 'diff by ranged tree:path' '
 test_expect_success 'index of ranged tree:path diff' '
 	check_index $sha1_one $sha1_two
 '
-test_expect_failure 'ranged tree:path diff uses filenames as paths' '
+test_expect_success 'ranged tree:path diff uses filenames as paths' '
 	check_paths one two
 '
 test_expect_success 'ranged tree:path diff shows mode change' '