diff --git a/akka-actor/src/main/scala/akka/actor/AbstractFSM.scala b/akka-actor/src/main/scala/akka/actor/AbstractFSM.scala
index f616866cdf..59e0c40c7e 100644
--- a/akka-actor/src/main/scala/akka/actor/AbstractFSM.scala
+++ b/akka-actor/src/main/scala/akka/actor/AbstractFSM.scala
@@ -112,7 +112,7 @@ abstract class AbstractFSM[S, D] extends FSM[S, D] {
    * called, not only the first one matching.</b>
    */
   final def onTransition(transitionHandler: UnitApply2[S, S]): Unit =
-    onTransition(transitionHandler(_: S, _: S)) 
+    onTransition(transitionHandler(_: S, _: S))
 
   /**
    * Set handler which is called upon reception of unhandled messages. Calling
diff --git a/akka-cluster-sharding/src/main/scala/akka/cluster/sharding/ShardCoordinator.scala b/akka-cluster-sharding/src/main/scala/akka/cluster/sharding/ShardCoordinator.scala
index abc86a01aa..62832ed412 100644
--- a/akka-cluster-sharding/src/main/scala/akka/cluster/sharding/ShardCoordinator.scala
+++ b/akka-cluster-sharding/src/main/scala/akka/cluster/sharding/ShardCoordinator.scala
@@ -801,8 +801,6 @@ class DDataShardCoordinator(typeName: String, settings: ClusterShardingSettings,
 
   node.subscribe(self, ClusterShuttingDown.getClass)
 
-  var afterUpdateCallback: DomainEvent ⇒ Unit = _
-
   // get state from ddata replicator, repeat until GetSuccess
   getState()
 
@@ -812,8 +810,9 @@ class DDataShardCoordinator(typeName: String, settings: ClusterShardingSettings,
   def waitingForState: Receive = ({
     case g @ GetSuccess(CoordinatorStateKey, _) ⇒
       state = g.get(CoordinatorStateKey).value
-      watchStateActors()
       context.become(waitingForStateInitialized)
+      // note that watchStateActors may call update
+      watchStateActors()
 
     case GetFailure(CoordinatorStateKey, _) ⇒
       log.error(
@@ -840,10 +839,12 @@ class DDataShardCoordinator(typeName: String, settings: ClusterShardingSettings,
   }
 
   // this state will stash all messages until it receives UpdateSuccess
-  def waitingForUpdate[E <: DomainEvent](evt: E): Receive = {
+  def waitingForUpdate[E <: DomainEvent](evt: E, afterUpdateCallback: DomainEvent ⇒ Unit): Receive = {
     case UpdateSuccess(CoordinatorStateKey, Some(`evt`)) ⇒
       log.debug("The coordinator state was successfully updated with {}", evt)
-      updateSuccess(evt)
+      context.unbecome()
+      afterUpdateCallback(evt)
+      unstashAll()
 
     case UpdateTimeout(CoordinatorStateKey, Some(`evt`)) ⇒
       log.error(
@@ -870,18 +871,10 @@ class DDataShardCoordinator(typeName: String, settings: ClusterShardingSettings,
   }
 
   def update[E <: DomainEvent](evt: E)(f: E ⇒ Unit): Unit = {
-    afterUpdateCallback = f.asInstanceOf[DomainEvent ⇒ Unit]
-    context.become(waitingForUpdate(evt))
+    context.become(waitingForUpdate(evt, f.asInstanceOf[DomainEvent ⇒ Unit]), discardOld = false)
     sendUpdate(evt)
   }
 
-  def updateSuccess(evt: DomainEvent): Unit = {
-    afterUpdateCallback(evt)
-    afterUpdateCallback = null
-    context.become(active)
-    unstashAll()
-  }
-
   def getState(): Unit =
     replicator ! Get(CoordinatorStateKey, ReadMajority(waitingForStateTimeout))
 
diff --git a/akka-cluster-sharding/src/multi-jvm/scala/akka/cluster/sharding/ClusterShardingGracefulShutdownSpec.scala b/akka-cluster-sharding/src/multi-jvm/scala/akka/cluster/sharding/ClusterShardingGracefulShutdownSpec.scala
index f6b9164445..52078bd474 100644
--- a/akka-cluster-sharding/src/multi-jvm/scala/akka/cluster/sharding/ClusterShardingGracefulShutdownSpec.scala
+++ b/akka-cluster-sharding/src/multi-jvm/scala/akka/cluster/sharding/ClusterShardingGracefulShutdownSpec.scala
@@ -9,9 +9,9 @@ import akka.actor._
 import akka.cluster.Cluster
 import akka.cluster.sharding.ShardRegion.GracefulShutdown
 import akka.persistence.Persistence
-import akka.persistence.journal.leveldb.{SharedLeveldbJournal, SharedLeveldbStore}
+import akka.persistence.journal.leveldb.{ SharedLeveldbJournal, SharedLeveldbStore }
 import akka.remote.testconductor.RoleName
-import akka.remote.testkit.{MultiNodeConfig, MultiNodeSpec, STMultiNodeSpec}
+import akka.remote.testkit.{ MultiNodeConfig, MultiNodeSpec, STMultiNodeSpec }
 import akka.testkit._
 import com.typesafe.config.ConfigFactory
 import org.apache.commons.io.FileUtils
diff --git a/project/MiMa.scala b/project/MiMa.scala
index f874b17ec8..a552a6a433 100644
--- a/project/MiMa.scala
+++ b/project/MiMa.scala
@@ -574,7 +574,10 @@ object MiMa extends AutoPlugin {
 
         //#18353 Changes to methods and fields private to remoting actors
         ProblemFilters.exclude[MissingMethodProblem]("akka.remote.EndpointManager.retryGateEnabled"),
-        ProblemFilters.exclude[IncompatibleResultTypeProblem]("akka.remote.EndpointManager.pruneTimerCancellable")
+        ProblemFilters.exclude[IncompatibleResultTypeProblem]("akka.remote.EndpointManager.pruneTimerCancellable"),
+        
+        // #18722 internal changes to actor
+        FilterAnyProblem("akka.cluster.sharding.DDataShardCoordinator")
       )
     )
   }