diff --git a/src/backend/commands/explain.c b/src/backend/commands/explain.c
index 67bdcb2b27..a131d15ac0 100644
--- a/src/backend/commands/explain.c
+++ b/src/backend/commands/explain.c
@@ -1456,7 +1456,8 @@ ExplainNode(PlanState *planstate, List *ancestors,
 				explain_get_index_name(bitmapindexscan->indexid);
 
 				if (es->format == EXPLAIN_FORMAT_TEXT)
-					appendStringInfo(es->str, " on %s", indexname);
+					appendStringInfo(es->str, " on %s",
+									 quote_identifier(indexname));
 				else
 					ExplainPropertyText("Index Name", indexname, es);
 			}
@@ -3267,6 +3268,10 @@ show_eval_params(Bitmapset *bms_params, ExplainState *es)
  *
  * We allow plugins to get control here so that plans involving hypothetical
  * indexes can be explained.
+ *
+ * Note: names returned by this function should be "raw"; the caller will
+ * apply quoting if needed.  Formerly the convention was to do quoting here,
+ * but we don't want that in non-text output formats.
  */
 static const char *
 explain_get_index_name(Oid indexId)
@@ -3279,11 +3284,10 @@ explain_get_index_name(Oid indexId)
 		result = NULL;
 	if (result == NULL)
 	{
-		/* default behavior: look in the catalogs and quote it */
+		/* default behavior: look it up in the catalogs */
 		result = get_rel_name(indexId);
 		if (result == NULL)
 			elog(ERROR, "cache lookup failed for index %u", indexId);
-		result = quote_identifier(result);
 	}
 	return result;
 }
@@ -3463,7 +3467,7 @@ ExplainIndexScanDetails(Oid indexid, ScanDirection indexorderdir,
 	{
 		if (ScanDirectionIsBackward(indexorderdir))
 			appendStringInfoString(es->str, " Backward");
-		appendStringInfo(es->str, " using %s", indexname);
+		appendStringInfo(es->str, " using %s", quote_identifier(indexname));
 	}
 	else
 	{