diff --git a/server/src/main/java/org/elasticsearch/action/bulk/TransportBulkAction.java b/server/src/main/java/org/elasticsearch/action/bulk/TransportBulkAction.java
index dce0a3325bce1..7dd3c3b324562 100644
--- a/server/src/main/java/org/elasticsearch/action/bulk/TransportBulkAction.java
+++ b/server/src/main/java/org/elasticsearch/action/bulk/TransportBulkAction.java
@@ -159,6 +159,9 @@ public TransportBulkAction(
         this.indexingPressure = indexingPressure;
         this.systemIndices = systemIndices;
         clusterService.addStateApplier(this.ingestForwarder);
+
+        assert bulkRequestPreprocessors.get(bulkRequestPreprocessors.size() - 1) instanceof FieldInferenceBulkRequestPreprocessor
+            : "Last bulk request processor should be the inference processor";
     }
 
     /**