diff --git a/src/borg/cache.py b/src/borg/cache.py
index 520e66a9d..e343ac745 100644
--- a/src/borg/cache.py
+++ b/src/borg/cache.py
@@ -1002,10 +1002,10 @@ def chunk_incref(self, id, stats, size_=None):
         if not self._txn_active:
             self._begin_txn()
         count, size, csize = self.chunks.incref(id)
-        stats.update(size or size_, csize, False)
         # When size is 0 and size_ is not given, then this chunk has not been locally visited yet (seen_chunk with
         # size or add_chunk); we can't add references to those (size=0 is invalid) and generally don't try to.
         assert size or size_
+        stats.update(size or size_, csize, False)
         return ChunkListEntry(id, size or size_, csize)
 
     def chunk_decref(self, id, stats, wait=True):