diff --git a/modules/calcite/src/main/java/org/apache/ignite/internal/processors/query/calcite/exec/ExecutionServiceImpl.java b/modules/calcite/src/main/java/org/apache/ignite/internal/processors/query/calcite/exec/ExecutionServiceImpl.java
index 70bc993f8b7e2..5dccd8fe10fda 100644
--- a/modules/calcite/src/main/java/org/apache/ignite/internal/processors/query/calcite/exec/ExecutionServiceImpl.java
+++ b/modules/calcite/src/main/java/org/apache/ignite/internal/processors/query/calcite/exec/ExecutionServiceImpl.java
@@ -537,7 +537,7 @@ private FragmentPlan prepareFragment(BaseQueryContext ctx, String jsonFragment)
                 );
 
             case EXPLAIN:
-                return executeExplain(qry, (ExplainPlan)plan);
+                return executeExplain((ExplainPlan)plan);
 
             case DDL:
                 return executeDdl(qry, (DdlPlan)plan);
@@ -883,7 +883,7 @@ private IgniteRel authorize(IgniteRel rel, IgniteTable.Operation op) {
     }
 
     /** */
-    private FieldsQueryCursor<List<?>> executeExplain(RootQuery<Row> qry, ExplainPlan plan) {
+    private FieldsQueryCursor<List<?>> executeExplain(ExplainPlan plan) {
         QueryCursorImpl<List<?>> cur = new QueryCursorImpl<>(singletonList(singletonList(plan.plan())));
         cur.fieldsMeta(plan.fieldsMeta().queryFieldsMetadata(Commons.typeFactory()));
 
diff --git a/modules/calcite/src/main/java/org/apache/ignite/internal/processors/query/calcite/metadata/FragmentDescription.java b/modules/calcite/src/main/java/org/apache/ignite/internal/processors/query/calcite/metadata/FragmentDescription.java
index 7560be273c184..4cbb2f34faa62 100644
--- a/modules/calcite/src/main/java/org/apache/ignite/internal/processors/query/calcite/metadata/FragmentDescription.java
+++ b/modules/calcite/src/main/java/org/apache/ignite/internal/processors/query/calcite/metadata/FragmentDescription.java
@@ -20,13 +20,12 @@
 import java.util.List;
 import java.util.Map;
 import java.util.UUID;
-import org.apache.ignite.IgniteCheckedException;
-import org.apache.ignite.internal.MarshallableMessage;
 import org.apache.ignite.internal.Order;
-import org.apache.ignite.marshaller.Marshaller;
+import org.apache.ignite.plugin.extensions.communication.Message;
+import org.jetbrains.annotations.Nullable;
 
 /** */
-public class FragmentDescription implements MarshallableMessage {
+public class FragmentDescription implements Message {
     /** */
     @Order(0)
     long fragmentId;
@@ -41,7 +40,7 @@ public class FragmentDescription implements MarshallableMessage {
 
     /** */
     @Order(3)
-    ColocationGroup target;
+    @Nullable ColocationGroup target;
 
     /** */
     public FragmentDescription() {
@@ -49,12 +48,14 @@ public FragmentDescription() {
     }
 
     /** */
-    public FragmentDescription(long fragmentId, FragmentMapping mapping, ColocationGroup target,
+    public FragmentDescription(long fragmentId, FragmentMapping mapping, @Nullable ColocationGroup target,
         Map<Long, List<UUID>> remoteSources) {
         this.fragmentId = fragmentId;
         this.mapping = mapping;
-        this.target = target;
         this.remoteSources = remoteSources;
+
+        if (target != null)
+            this.target = target.explicitMapping();
     }
 
     /** */
@@ -73,7 +74,7 @@ public List<UUID> nodeIds() {
     }
 
     /** */
-    public ColocationGroup target() {
+    public @Nullable ColocationGroup target() {
         return target;
     }
 
@@ -96,15 +97,4 @@ public FragmentMapping mapping() {
     public void mapping(FragmentMapping mapping) {
         this.mapping = mapping;
     }
-
-    /** */
-    @Override public void prepareMarshal(Marshaller marsh) throws IgniteCheckedException {
-        if (target != null)
-            target = target.explicitMapping();
-    }
-
-    /** */
-    @Override public void finishUnmarshal(Marshaller marsh, ClassLoader clsLdr) throws IgniteCheckedException {
-        // No-op.
-    }
 }
diff --git a/modules/calcite/src/main/java/org/apache/ignite/internal/processors/query/calcite/prepare/ExecutionPlan.java b/modules/calcite/src/main/java/org/apache/ignite/internal/processors/query/calcite/prepare/ExecutionPlan.java
index 8a7058d7b09de..8338e731e6998 100644
--- a/modules/calcite/src/main/java/org/apache/ignite/internal/processors/query/calcite/prepare/ExecutionPlan.java
+++ b/modules/calcite/src/main/java/org/apache/ignite/internal/processors/query/calcite/prepare/ExecutionPlan.java
@@ -30,6 +30,7 @@
 import org.apache.ignite.internal.processors.query.calcite.rel.IgniteSender;
 import org.apache.ignite.internal.util.typedef.F;
 import org.apache.ignite.internal.util.typedef.internal.U;
+import org.jetbrains.annotations.Nullable;
 
 /**
  *
@@ -72,7 +73,7 @@ public FragmentMapping mapping(Fragment fragment) {
     }
 
     /** */
-    public ColocationGroup target(Fragment fragment) {
+    public @Nullable ColocationGroup target(Fragment fragment) {
         if (fragment.rootFragment())
             return null;