diff --git a/sql/sql_select.cc b/sql/sql_select.cc
index 90a8727c56c3563497f4780aeb21e2f6b789e0a8..6e42b65175a8ad466d52a0f6bfb0d96ef7f50434 100644
--- a/sql/sql_select.cc
+++ b/sql/sql_select.cc
@@ -6504,7 +6504,6 @@ make_join_select(JOIN *join,SQL_SELECT *select,COND *cond)
               ((tab->type != JT_CONST && tab->type != JT_REF) ||
                (uint)tab->ref.key == tab->quick->index))
           {
-            DBUG_ASSERT(tab->quick->index != MAX_KEY);
 	    sel->quick=tab->quick;		// Use value from get_quick_...
 	    sel->quick_keys.clear_all();
 	    sel->needed_reg.clear_all();