diff --git a/lib/storage/dataset-clients.js b/lib/storage/dataset-clients.js
index 2c5b0ae..4e5eefe 100644
--- a/lib/storage/dataset-clients.js
+++ b/lib/storage/dataset-clients.js
@@ -154,6 +154,8 @@ function upsertOrDeleteDatasetRecords(datasetId, datasetClientId, records, cb) {
     } else if (op === 'delete') {
       //remove the ref
       update['$pull'] = {'refs': datasetClientId};
+      // also set the hash to null to handle race condition when multiple refs associated with single record
+      update['$set']['hash'] = null;
     }
     datasetRecordsCol.findOneAndUpdate({uid: record.uid}, update, {upsert: true, returnOriginal: false}, function(err, updated) {
       if (err) {