diff --git a/docs/reference/migration/migrate_6_5.asciidoc b/docs/reference/migration/migrate_6_5.asciidoc
index a6b22cf38d356..432fe999982c6 100644
--- a/docs/reference/migration/migrate_6_5.asciidoc
+++ b/docs/reference/migration/migrate_6_5.asciidoc
@@ -5,6 +5,7 @@ This section discusses the changes that you need to be aware of when migrating
 your application to Elasticsearch 6.5.
 
 * <<breaking_65_logging_changes>>
+* <<breaking_65_search_changes>>
 * <<breaking_65_sql_changes>>
 
 See also <<release-highlights>> and <<es-release-notes>>.
@@ -25,6 +26,16 @@ will not change the logging configuration files though. You should make this
 change before 7.0 because in 7.0 Elasticsearch will no longer automatically
 add the node name to the logging configuration if it isn't already present.
 
+[[breaking_65_search_changes]]
+=== Search changes
+
+==== Scroll
+
+Using `rescore` with a scroll query now raises a deprecation warning and
+ignores the parameter.  In earlier 6.x releases, rescore on scroll queries was
+silently ignored.  In 7.0 and later, we will return a `400 - Bad Request` with
+a validation error.
+
 [[breaking_65_sql_changes]]
 === SQL plugin changes
 
diff --git a/server/src/main/java/org/elasticsearch/action/search/SearchRequest.java b/server/src/main/java/org/elasticsearch/action/search/SearchRequest.java
index 05b06e65dea65..105d5d3aa7b08 100644
--- a/server/src/main/java/org/elasticsearch/action/search/SearchRequest.java
+++ b/server/src/main/java/org/elasticsearch/action/search/SearchRequest.java
@@ -137,6 +137,10 @@ public ActionRequestValidationException validate() {
         if (source != null && source.size() == 0 && scroll != null) {
             validationException = addValidationError("[size] cannot be [0] in a scroll context", validationException);
         }
+        if (source != null && source.rescores() != null && source.rescores().isEmpty() == false && scroll != null) {
+            DEPRECATION_LOGGER.deprecated("Using [rescore] for a scroll query is deprecated and will be ignored. From 7.0 on will " +
+                    "return a 400 error");
+        }
         return validationException;
     }
 
diff --git a/server/src/test/java/org/elasticsearch/search/SearchRequestTests.java b/server/src/test/java/org/elasticsearch/search/SearchRequestTests.java
index eb2018f40c0a9..6fc0816168688 100644
--- a/server/src/test/java/org/elasticsearch/search/SearchRequestTests.java
+++ b/server/src/test/java/org/elasticsearch/search/SearchRequestTests.java
@@ -28,7 +28,9 @@
 import org.elasticsearch.common.io.stream.StreamInput;
 import org.elasticsearch.common.unit.TimeValue;
 import org.elasticsearch.common.util.ArrayUtils;
+import org.elasticsearch.index.query.QueryBuilders;
 import org.elasticsearch.search.builder.SearchSourceBuilder;
+import org.elasticsearch.search.rescore.QueryRescorerBuilder;
 
 import java.io.IOException;
 import java.util.ArrayList;
@@ -124,6 +126,17 @@ public void testValidate() throws IOException {
             assertEquals(1, validationErrors.validationErrors().size());
             assertEquals("[size] cannot be [0] in a scroll context", validationErrors.validationErrors().get(0));
         }
+        {
+            // Rescore is deprecated on scroll requests
+            SearchRequest searchRequest = createSearchRequest().source(new SearchSourceBuilder());
+            searchRequest.source().addRescorer(new QueryRescorerBuilder(QueryBuilders.matchAllQuery()));
+            searchRequest.requestCache(false);
+            searchRequest.scroll(new TimeValue(1000));
+            ActionRequestValidationException validationErrors = searchRequest.validate();
+            assertNull(validationErrors);
+            assertWarnings("Using [rescore] for a scroll query is deprecated and will be ignored. From 7.0 on will return a 400 error");
+        }
+
     }
 
     public void testEqualsAndHashcode() throws IOException {