diff --git a/src/test/regress/pg_regress.c b/src/test/regress/pg_regress.c
index a4caa228e28..10111ebfb91 100644
--- a/src/test/regress/pg_regress.c
+++ b/src/test/regress/pg_regress.c
@@ -1454,20 +1454,23 @@ results_differ(const char *testname, const char *resultsfile, const char *defaul
 	 * Use the best comparison file to generate the "pretty" diff, which we
 	 * append to the diffs summary file.
 	 */
-	snprintf(cmd, sizeof(cmd),
-			 "diff %s \"%s\" \"%s\" >> \"%s\"",
-			 pretty_diff_opts, best_expect_file, resultsfile, difffilename);
-	run_diff(cmd, difffilename);
 
-	/* And append a separator */
+	/* Write diff header */
 	difffile = fopen(difffilename, "a");
 	if (difffile)
 	{
 		fprintf(difffile,
-				"\n======================================================================\n\n");
+				"diff %s %s %s\n",
+				pretty_diff_opts, best_expect_file, resultsfile);
 		fclose(difffile);
 	}
 
+	/* Run diff */
+	snprintf(cmd, sizeof(cmd),
+			 "diff %s \"%s\" \"%s\" >> \"%s\"",
+			 pretty_diff_opts, best_expect_file, resultsfile, difffilename);
+	run_diff(cmd, difffilename);
+
 	unlink(diff);
 	return true;
 }