diff --git a/src/backend/rewrite/rewriteManip.c b/src/backend/rewrite/rewriteManip.c
index ed1c07bb5e7..ddc222d6913 100644
--- a/src/backend/rewrite/rewriteManip.c
+++ b/src/backend/rewrite/rewriteManip.c
@@ -549,7 +549,9 @@ offset_relid_set(Relids relids, int offset)
  * Also, new_index can be INVALID_VAR to indicate that we are deleting the
  * given relid from the tree.  In this case we expect to find rt_index only
  * in Relids fields (varnullingrels, phnullingrels, phrels), never in any
- * field that identifies a single relation.
+ * field that identifies a single relation.  The exception is varnosyn,
+ * which may name an aliased join being removed; the join's RTE remains in
+ * the rangetable, so we leave such syntactic references unchanged.
  *
  * NOTE: although this has the form of a walker, we cheat and modify the
  * nodes in-place.  The given expression tree should have been copied
@@ -582,11 +584,10 @@ ChangeVarNodes_walker(Node *node, ChangeVarNodes_context *context)
 			var->varnullingrels = adjust_relid_set(var->varnullingrels,
 												   context->rt_index,
 												   context->new_index);
-			if (var->varnosyn == context->rt_index)
-			{
-				Assert(context->new_index != INVALID_VAR);
+			/* when deleting, leave syntactic refs to a removed join alone */
+			if (var->varnosyn == context->rt_index &&
+				context->new_index != INVALID_VAR)
 				var->varnosyn = context->new_index;
-			}
 		}
 		return false;
 	}
diff --git a/src/test/regress/expected/join.out b/src/test/regress/expected/join.out
index 37ac979e74e..4b31d9e6957 100644
--- a/src/test/regress/expected/join.out
+++ b/src/test/regress/expected/join.out
@@ -6266,6 +6266,18 @@ select c.id, ss.a from c
          ->  Seq Scan on c
 (7 rows)
 
+-- check join removal when Vars reference the removed join via its alias
+explain (verbose, costs off)
+select j.b_id, (select j.b_id) from (a left join b on a.b_id = b.id) j;
+          QUERY PLAN           
+-------------------------------
+ Seq Scan on pg_temp.a
+   Output: a.b_id, (SubPlan 1)
+   SubPlan 1
+     ->  Result
+           Output: a.b_id
+(5 rows)
+
 CREATE TEMP TABLE parted_b (id int PRIMARY KEY) partition by range(id);
 CREATE TEMP TABLE parted_b1 partition of parted_b for values from (0) to (10);
 -- test join removals on a partitioned table
diff --git a/src/test/regress/sql/join.sql b/src/test/regress/sql/join.sql
index fc984fff672..90023903077 100644
--- a/src/test/regress/sql/join.sql
+++ b/src/test/regress/sql/join.sql
@@ -2287,6 +2287,10 @@ select c.id, ss.a from c
   left join (select d.a from onerow, d left join b on d.a = b.id) ss
   on c.id = ss.a;
 
+-- check join removal when Vars reference the removed join via its alias
+explain (verbose, costs off)
+select j.b_id, (select j.b_id) from (a left join b on a.b_id = b.id) j;
+
 CREATE TEMP TABLE parted_b (id int PRIMARY KEY) partition by range(id);
 CREATE TEMP TABLE parted_b1 partition of parted_b for values from (0) to (10);