diff --git a/src/backend/storage/smgr/smgr.c b/src/backend/storage/smgr/smgr.c
index a477f70f0e3..631733bb660 100644
--- a/src/backend/storage/smgr/smgr.c
+++ b/src/backend/storage/smgr/smgr.c
@@ -292,6 +292,7 @@ smgrrelease(SMgrRelation reln)
 		smgrsw[reln->smgr_which].smgr_close(reln, forknum);
 		reln->smgr_cached_nblocks[forknum] = InvalidBlockNumber;
 	}
+	reln->smgr_targblock = InvalidBlockNumber;
 }
 
 /*