diff --git a/elasticsearch/src/main/java/org/elasticsearch/xpack/prelert/rest/results/RestGetBucketsAction.java b/elasticsearch/src/main/java/org/elasticsearch/xpack/prelert/rest/results/RestGetBucketsAction.java
index 240356f1973..cb72f002aa9 100644
--- a/elasticsearch/src/main/java/org/elasticsearch/xpack/prelert/rest/results/RestGetBucketsAction.java
+++ b/elasticsearch/src/main/java/org/elasticsearch/xpack/prelert/rest/results/RestGetBucketsAction.java
@@ -51,47 +51,41 @@ public class RestGetBucketsAction extends BaseRestHandler {
             request = GetBucketsAction.Request.parseRequest(jobId, parser, () -> parseFieldMatcher);
         } else {
             request = new GetBucketsAction.Request(jobId);
-            String timestamp = restRequest.param(GetBucketsAction.Request.TIMESTAMP.getPreferredName());
 
-            // Single bucket
-            if (timestamp != null && !timestamp.isEmpty()) {
-                request.setTimestamp(timestamp);
+            // Check if the REST param is set first so mutually exclusive
+            // options will only cause an error if set
+            if (restRequest.hasParam(GetBucketsAction.Request.TIMESTAMP.getPreferredName())) {
+                String timestamp = restRequest.param(GetBucketsAction.Request.TIMESTAMP.getPreferredName());
+                if (timestamp != null && !timestamp.isEmpty()) {
+                    request.setTimestamp(timestamp);
+                }
             }
-            if (restRequest.hasParam(PageParams.FROM.getPreferredName())
-                    || restRequest.hasParam(PageParams.SIZE.getPreferredName())
-                    || restRequest.hasParam(GetBucketsAction.Request.START.getPreferredName())
-                    || restRequest.hasParam(GetBucketsAction.Request.END.getPreferredName())
-                    || restRequest.hasParam(GetBucketsAction.Request.ANOMALY_SCORE.getPreferredName())
-                    || restRequest.hasParam(GetBucketsAction.Request.MAX_NORMALIZED_PROBABILITY.getPreferredName())
-                    || timestamp == null) {
-
+            // multiple bucket options
+            if (restRequest.hasParam(PageParams.FROM.getPreferredName()) || restRequest.hasParam(PageParams.SIZE.getPreferredName())) {
                 request.setPageParams(
                         new PageParams(restRequest.paramAsInt(PageParams.FROM.getPreferredName(), PageParams.DEFAULT_FROM),
                                 restRequest.paramAsInt(PageParams.SIZE.getPreferredName(), PageParams.DEFAULT_SIZE)));
-
-                // Multiple buckets, check if the param is set first so mutually exclusive
-                // options will only cause an error if set
-                if (restRequest.hasParam(GetBucketsAction.Request.START.getPreferredName())) {
-                    request.setStart(restRequest.param(GetBucketsAction.Request.START.getPreferredName()));
-                }
-                if (restRequest.hasParam(GetBucketsAction.Request.END.getPreferredName())) {
-                    request.setEnd(restRequest.param(GetBucketsAction.Request.END.getPreferredName()));
-                }
-                if (restRequest.hasParam(GetBucketsAction.Request.ANOMALY_SCORE.getPreferredName())) {
-                    request.setAnomalyScore(
-                            Double.parseDouble(restRequest.param(GetBucketsAction.Request.ANOMALY_SCORE.getPreferredName(), "0.0")));
-                }
-                if (restRequest.hasParam(GetBucketsAction.Request.MAX_NORMALIZED_PROBABILITY.getPreferredName())) {
-                    request.setMaxNormalizedProbability(
-                            Double.parseDouble(restRequest.param(
-                                    GetBucketsAction.Request.MAX_NORMALIZED_PROBABILITY.getPreferredName(), "0.0")));
-                }
-                if (restRequest.hasParam(GetBucketsAction.Request.PARTITION_VALUE.getPreferredName())) {
-                    request.setPartitionValue(restRequest.param(GetBucketsAction.Request.PARTITION_VALUE.getPreferredName()));
-                }
+            }
+            if (restRequest.hasParam(GetBucketsAction.Request.START.getPreferredName())) {
+                request.setStart(restRequest.param(GetBucketsAction.Request.START.getPreferredName()));
+            }
+            if (restRequest.hasParam(GetBucketsAction.Request.END.getPreferredName())) {
+                request.setEnd(restRequest.param(GetBucketsAction.Request.END.getPreferredName()));
+            }
+            if (restRequest.hasParam(GetBucketsAction.Request.ANOMALY_SCORE.getPreferredName())) {
+                request.setAnomalyScore(
+                        Double.parseDouble(restRequest.param(GetBucketsAction.Request.ANOMALY_SCORE.getPreferredName(), "0.0")));
+            }
+            if (restRequest.hasParam(GetBucketsAction.Request.MAX_NORMALIZED_PROBABILITY.getPreferredName())) {
+                request.setMaxNormalizedProbability(
+                        Double.parseDouble(restRequest.param(
+                                GetBucketsAction.Request.MAX_NORMALIZED_PROBABILITY.getPreferredName(), "0.0")));
+            }
+            if (restRequest.hasParam(GetBucketsAction.Request.PARTITION_VALUE.getPreferredName())) {
+                request.setPartitionValue(restRequest.param(GetBucketsAction.Request.PARTITION_VALUE.getPreferredName()));
             }
 
-            // Common options
+            // single and multiple bucket options
             request.setExpand(restRequest.paramAsBoolean(GetBucketsAction.Request.EXPAND.getPreferredName(), false));
             request.setIncludeInterim(restRequest.paramAsBoolean(GetBucketsAction.Request.INCLUDE_INTERIM.getPreferredName(), false));
         }
diff --git a/elasticsearch/src/test/resources/rest-api-spec/test/jobs_get_result_buckets.yaml b/elasticsearch/src/test/resources/rest-api-spec/test/jobs_get_result_buckets.yaml
index ec1c9b3206a..fb51233458d 100644
--- a/elasticsearch/src/test/resources/rest-api-spec/test/jobs_get_result_buckets.yaml
+++ b/elasticsearch/src/test/resources/rest-api-spec/test/jobs_get_result_buckets.yaml
@@ -99,6 +99,13 @@ setup:
         timestamp: "2016-06-01T00:00:00Z"
         end: "2016-05-01T00:00:00Z"
 
+  - do:
+      catch: request
+      xpack.ml.get_buckets:
+        job_id: "farequote"
+        timestamp: "2016-06-01T00:00:00Z"
+        anomaly_score: "80.0"
+
 ---
 "Test mutually-exclusive params (via body)":
   - do:
@@ -132,3 +139,11 @@ setup:
         body:
           timestamp: "2016-06-01T00:00:00Z"
           end: "2016-05-01T00:00:00Z"
+
+  - do:
+      catch: request
+      xpack.ml.get_buckets:
+        job_id: "farequote"
+        body:
+          timestamp: "2016-06-01T00:00:00Z"
+          anomaly_score: "80.0"