diff --git a/btr/btr0btr.c b/btr/btr0btr.c
index e2093a8df08..5d694d4fbe8 100644
--- a/btr/btr0btr.c
+++ b/btr/btr0btr.c
@@ -2509,6 +2509,11 @@ btr_discard_page(
 
 		ut_ad(page_rec_is_user_rec(node_ptr));
 
+		/* This will make page_zip_validate() fail on merge_page
+		until btr_level_list_remove() completes.  This is harmless,
+		because everything will take place within a single
+		mini-transaction and because writing to the redo log
+		is an atomic operation (performed by mtr_commit()). */
 		btr_set_min_rec_mark(node_ptr, mtr);
 	}
 
@@ -2516,6 +2521,14 @@ btr_discard_page(
 
 	/* Remove the page from the level list */
 	btr_level_list_remove(tree, page, mtr);
+#if defined UNIV_DEBUG || defined UNIV_ZIP_DEBUG
+	{
+		page_zip_des_t*	merge_page_zip = buf_block_get_page_zip(
+						buf_block_align(merge_page));
+		ut_a(!merge_page_zip
+			|| page_zip_validate(merge_page_zip, merge_page));
+	}
+#endif /* UNIV_DEBUG || UNIV_ZIP_DEBUG */
 
 	if (left_page_no != FIL_NULL) {
 		lock_update_discard(page_get_supremum_rec(merge_page), page);
diff --git a/btr/btr0cur.c b/btr/btr0cur.c
index 0a81100720e..cdb2ecb2f52 100644
--- a/btr/btr0cur.c
+++ b/btr/btr0cur.c
@@ -1766,6 +1766,9 @@ btr_cur_optimistic_update(
 	new_rec_size = rec_get_converted_size(index, new_entry);
 
 	page_zip = buf_block_get_page_zip(buf_block_align(page));
+#if defined UNIV_DEBUG || defined UNIV_ZIP_DEBUG
+	ut_a(!page_zip || page_zip_validate(page_zip, page));
+#endif /* UNIV_DEBUG || UNIV_ZIP_DEBUG */
 
 	if (UNIV_LIKELY_NULL(page_zip)
 			&& !page_zip_alloc(page_zip, page, index,
@@ -1968,6 +1971,9 @@ btr_cur_pessimistic_update(
 							MTR_MEMO_X_LOCK));
 	ut_ad(mtr_memo_contains(mtr, buf_block_align(page),
 							MTR_MEMO_PAGE_X_FIX));
+#if defined UNIV_DEBUG || defined UNIV_ZIP_DEBUG
+	ut_a(!page_zip || page_zip_validate(page_zip, page));
+#endif /* UNIV_DEBUG || UNIV_ZIP_DEBUG */
 
 	optim_err = btr_cur_optimistic_update(flags, cursor, update,
 							cmpl_info, thr, mtr);
@@ -2085,6 +2091,9 @@ btr_cur_pessimistic_update(
 
 	btr_search_update_hash_on_delete(cursor);
 
+#if defined UNIV_DEBUG || defined UNIV_ZIP_DEBUG
+	ut_a(!page_zip || page_zip_validate(page_zip, page));
+#endif /* UNIV_DEBUG || UNIV_ZIP_DEBUG */
 	page_cur_delete_rec(page_cursor, index, offsets, page_zip, mtr);
 
 	page_cur_move_to_prev(page_cursor);
@@ -2604,17 +2613,24 @@ btr_cur_optimistic_delete(
 
 	if (no_compress_needed) {
 
+		page_zip_des_t*	page_zip;
+
 		lock_update_delete(rec);
 
 		btr_search_update_hash_on_delete(cursor);
 
 		max_ins_size = page_get_max_insert_size_after_reorganize(page,
 									1);
+		page_zip = buf_block_get_page_zip(buf_block_align(
+					btr_cur_get_rec(cursor)));
+#if defined UNIV_DEBUG || defined UNIV_ZIP_DEBUGp
+		ut_a(!page_zip || page_zip_validate(page_zip, page));
+#endif /* UNIV_DEBUG || UNIV_ZIP_DEBUG */
 		page_cur_delete_rec(btr_cur_get_page_cur(cursor),
-				cursor->index, offsets,
-				buf_block_get_page_zip(buf_block_align(
-					btr_cur_get_rec(cursor))),
-				mtr);
+				cursor->index, offsets, page_zip, mtr);
+#if defined UNIV_DEBUG || defined UNIV_ZIP_DEBUGp
+		ut_a(!page_zip || page_zip_validate(page_zip, page));
+#endif /* UNIV_DEBUG || UNIV_ZIP_DEBUG */
 
 		ibuf_update_free_bits_low(cursor->index, page, max_ins_size,
 									mtr);
@@ -2695,6 +2711,9 @@ btr_cur_pessimistic_delete(
 	heap = mem_heap_create(1024);
 	rec = btr_cur_get_rec(cursor);
 	page_zip = buf_block_get_page_zip(buf_block_align(page));
+#if defined UNIV_DEBUG || defined UNIV_ZIP_DEBUG
+	ut_a(!page_zip || page_zip_validate(page_zip, page));
+#endif /* UNIV_DEBUG || UNIV_ZIP_DEBUG */
 
 	offsets = rec_get_offsets(rec, cursor->index,
 					NULL, ULINT_UNDEFINED, &heap);
@@ -2707,6 +2726,9 @@ btr_cur_pessimistic_delete(
 			|| !rec_get_1byte_offs_flag(rec))) {
 		btr_rec_free_externally_stored_fields(cursor->index, rec,
 					offsets, page_zip, in_rollback, mtr);
+#if defined UNIV_DEBUG || defined UNIV_ZIP_DEBUGp
+		ut_a(!page_zip || page_zip_validate(page_zip, page));
+#endif /* UNIV_DEBUG || UNIV_ZIP_DEBUG */
 	}
 
 	if (UNIV_UNLIKELY(page_get_n_recs(page) < 2)
@@ -2739,6 +2761,11 @@ btr_cur_pessimistic_delete(
 			non-leaf level, we must mark the new leftmost node
 			pointer as the predefined minimum record */
 
+			/* This will make page_zip_validate() fail until
+			page_cur_delete_rec() completes.  This is harmless,
+			because everything will take place within a single
+			mini-transaction and because writing to the redo log
+			is an atomic operation (performed by mtr_commit()). */
 			btr_set_min_rec_mark(next_rec, mtr);
 		} else {
 			/* Otherwise, if we delete the leftmost node pointer
@@ -2762,6 +2789,9 @@ btr_cur_pessimistic_delete(
 
 	page_cur_delete_rec(btr_cur_get_page_cur(cursor), cursor->index,
 						offsets, page_zip, mtr);
+#if defined UNIV_DEBUG || defined UNIV_ZIP_DEBUGp
+	ut_a(!page_zip || page_zip_validate(page_zip, page));
+#endif /* UNIV_DEBUG || UNIV_ZIP_DEBUG */
 
 	ut_ad(btr_check_node_ptr(tree, page, mtr));
 
diff --git a/page/page0cur.c b/page/page0cur.c
index 82f63da65df..9d0d191f4ec 100644
--- a/page/page0cur.c
+++ b/page/page0cur.c
@@ -1514,9 +1514,6 @@ page_cur_delete_rec(
 	current_rec = cursor->rec;
 	ut_ad(rec_offs_validate(current_rec, index, offsets));
 	ut_ad(!!page_is_comp(page) == dict_table_is_comp(index->table));
-#if defined UNIV_DEBUG || defined UNIV_ZIP_DEBUG
-	ut_a(!page_zip || page_zip_validate(page_zip, page));
-#endif /* UNIV_DEBUG || UNIV_ZIP_DEBUG */
 
 	/* The record must not be the supremum or infimum record. */
 	ut_ad(page_rec_is_user_rec(current_rec));
diff --git a/page/page0page.c b/page/page0page.c
index 15a0271154e..d70fc14bf36 100644
--- a/page/page0page.c
+++ b/page/page0page.c
@@ -831,7 +831,7 @@ page_delete_rec_list_end(
 	rec_t*		last_rec;
 	rec_t*		prev_rec;
 	ulint		n_owned;
-	page_t*		page;
+	page_t*		page		= ut_align_down(rec, UNIV_PAGE_SIZE);
 	mem_heap_t*	heap		= NULL;
 	ulint		offsets_[REC_OFFS_NORMAL_SIZE];
 	ulint*		offsets		= offsets_;
@@ -839,6 +839,9 @@ page_delete_rec_list_end(
 
 	ut_ad(size == ULINT_UNDEFINED || size < UNIV_PAGE_SIZE);
 	ut_ad(!page_zip || page_rec_is_comp(rec));
+#if defined UNIV_DEBUG || defined UNIV_ZIP_DEBUG
+	ut_a(!page_zip || page_zip_validate(page_zip, page));
+#endif /* UNIV_DEBUG || UNIV_ZIP_DEBUG */
 
 	if (page_rec_is_infimum(rec)) {
 		rec = page_rec_get_next(rec);
@@ -852,7 +855,6 @@ page_delete_rec_list_end(
 	/* Reset the last insert info in the page header and increment
 	the modify clock for the frame */
 
-	page = ut_align_down(rec, UNIV_PAGE_SIZE);
 	page_header_set_ptr(page, page_zip, PAGE_LAST_INSERT, NULL);
 
 	/* The page gets invalid for optimistic searches: increment the
@@ -1004,6 +1006,10 @@ page_delete_rec_list_start(
 
 	ut_ad((ibool) !!page_rec_is_comp(rec)
 			== dict_table_is_comp(index->table));
+#if defined UNIV_DEBUG || defined UNIV_ZIP_DEBUG
+	ut_a(!page_zip || page_zip_validate(page_zip,
+			ut_align_down(rec, UNIV_PAGE_SIZE)));
+#endif /* UNIV_DEBUG || UNIV_ZIP_DEBUG */
 
 	if (page_rec_is_infimum(rec)) {