diff --git a/enterprise-module/src/main/java/com/inteligr8/alfresco/asie/enterprise/service/ShardDiscoveryService.java b/enterprise-module/src/main/java/com/inteligr8/alfresco/asie/enterprise/service/ShardDiscoveryService.java
index cc0bd7e..60eeff4 100644
--- a/enterprise-module/src/main/java/com/inteligr8/alfresco/asie/enterprise/service/ShardDiscoveryService.java
+++ b/enterprise-module/src/main/java/com/inteligr8/alfresco/asie/enterprise/service/ShardDiscoveryService.java
@@ -264,7 +264,7 @@ public class ShardDiscoveryService implements com.inteligr8.alfresco.asie.spi.Sh
 				ShardInstanceState nodeShardState = ShardInstanceState.from(shardState);
 				
 				Pair<SolrHost, ShardInstanceState> pair = new Pair<>(node, nodeShardState);
-				if (comparator.compare(pair, shardNodeStates.get(shardId)) < 0)
+				if (!shardNodeStates.containsKey(shardId) || comparator.compare(pair, shardNodeStates.get(shardId)) < 0)
 					shardNodeStates.put(shardId, pair);
 			}
 		}
diff --git a/shared/src/main/java/com/inteligr8/alfresco/asie/spi/ShardDiscoveryService.java b/shared/src/main/java/com/inteligr8/alfresco/asie/spi/ShardDiscoveryService.java
index e947a15..284a3af 100644
--- a/shared/src/main/java/com/inteligr8/alfresco/asie/spi/ShardDiscoveryService.java
+++ b/shared/src/main/java/com/inteligr8/alfresco/asie/spi/ShardDiscoveryService.java
@@ -125,7 +125,9 @@ public interface ShardDiscoveryService {
 	public class ShardedNodeShardStateComparator implements Comparator<Pair<SolrHost, ShardInstanceState>> {
 		@Override
 		public int compare(Pair<SolrHost, ShardInstanceState> p1, Pair<SolrHost, ShardInstanceState> p2) {
-			return - Long.compare(p1.getSecond().getLastIndexedTxId(), p2.getSecond().getLastIndexedTxId());
+			if (p1 == null) return 1;
+			else if (p2 == null) return -1;
+			else return - Long.compare(p1.getSecond().getLastIndexedTxId(), p2.getSecond().getLastIndexedTxId());
 		}
 	}