diff --git a/crates/milli/src/update/new/extract/vectors/mod.rs b/crates/milli/src/update/new/extract/vectors/mod.rs
index 77bfc1206..2864475c9 100644
--- a/crates/milli/src/update/new/extract/vectors/mod.rs
+++ b/crates/milli/src/update/new/extract/vectors/mod.rs
@@ -175,16 +175,6 @@ impl<'extractor> Extractor<'extractor> for EmbeddingExtractor<'_, '_> {
                                 }
                             }
                         } else if old_vectors.regenerate {
-                            let old_rendered = prompt.render_document(
-                                update.external_document_id(),
-                                update.current(
-                                    &context.rtxn,
-                                    context.index,
-                                    context.db_fields_ids_map,
-                                )?,
-                                context.new_fields_ids_map,
-                                &context.doc_alloc,
-                            )?;
                             let new_rendered = prompt.render_document(
                                 update.external_document_id(),
                                 update.merged(
@@ -195,7 +185,28 @@ impl<'extractor> Extractor<'extractor> for EmbeddingExtractor<'_, '_> {
                                 context.new_fields_ids_map,
                                 &context.doc_alloc,
                             )?;
-                            if new_rendered != old_rendered {
+
+                            let must_regenerate = {
+                                let old_rendered = prompt.render_document(
+                                    update.external_document_id(),
+                                    update.current(
+                                        &context.rtxn,
+                                        context.index,
+                                        context.db_fields_ids_map,
+                                    )?,
+                                    context.new_fields_ids_map,
+                                    &context.doc_alloc,
+                                );
+                                if let Ok(old_rendered) = old_rendered {
+                                    // regenerate if the rendered version changed
+                                    new_rendered != old_rendered
+                                } else {
+                                    // if we cannot render the previous version of the documents, let's regenerate
+                                    true
+                                }
+                            };
+
+                            if must_regenerate {
                                 chunks.set_autogenerated(
                                     update.docid(),
                                     update.external_document_id(),