diff --git a/core/src/main/java/org/elasticsearch/action/get/MultiGetRequest.java b/core/src/main/java/org/elasticsearch/action/get/MultiGetRequest.java
index d4627391b11..20a619cec2c 100644
--- a/core/src/main/java/org/elasticsearch/action/get/MultiGetRequest.java
+++ b/core/src/main/java/org/elasticsearch/action/get/MultiGetRequest.java
@@ -44,6 +44,7 @@ import java.util.Arrays;
 import java.util.Collections;
 import java.util.Iterator;
 import java.util.List;
+import java.util.Locale;
 
 public class MultiGetRequest extends ActionRequest implements Iterable<MultiGetRequest.Item>, CompositeIndicesRequest, RealtimeRequest {
 
@@ -319,6 +320,14 @@ public class MultiGetRequest extends ActionRequest implements Iterable<MultiGetR
             boolean allowExplicitIndex) throws IOException {
         XContentParser.Token token;
         String currentFieldName = null;
+        if ((token = parser.nextToken()) != XContentParser.Token.START_OBJECT) {
+            final String message = String.format(
+                    Locale.ROOT,
+                    "unexpected token [%s], expected [%s]",
+                    token,
+                    XContentParser.Token.START_OBJECT);
+            throw new ParsingException(parser.getTokenLocation(), message);
+        }
         while ((token = parser.nextToken()) != XContentParser.Token.END_OBJECT) {
             if (token == XContentParser.Token.FIELD_NAME) {
                 currentFieldName = parser.currentName();
@@ -327,7 +336,22 @@ public class MultiGetRequest extends ActionRequest implements Iterable<MultiGetR
                     parseDocuments(parser, this.items, defaultIndex, defaultType, defaultFields, defaultFetchSource, defaultRouting, allowExplicitIndex);
                 } else if ("ids".equals(currentFieldName)) {
                     parseIds(parser, this.items, defaultIndex, defaultType, defaultFields, defaultFetchSource, defaultRouting);
+                } else {
+                    final String message = String.format(
+                            Locale.ROOT,
+                            "unknown key [%s] for a %s, expected [docs] or [ids]",
+                            currentFieldName,
+                            token);
+                    throw new ParsingException(parser.getTokenLocation(), message);
                 }
+            } else {
+                final String message = String.format(
+                        Locale.ROOT,
+                        "unexpected token [%s], expected [%s] or [%s]",
+                        token,
+                        XContentParser.Token.FIELD_NAME,
+                        XContentParser.Token.START_ARRAY);
+                throw new ParsingException(parser.getTokenLocation(), message);
             }
         }
         return this;
diff --git a/core/src/test/java/org/elasticsearch/action/get/MultiGetRequestTests.java b/core/src/test/java/org/elasticsearch/action/get/MultiGetRequestTests.java
index 6c79b20774c..4e539d8582f 100644
--- a/core/src/test/java/org/elasticsearch/action/get/MultiGetRequestTests.java
+++ b/core/src/test/java/org/elasticsearch/action/get/MultiGetRequestTests.java
@@ -19,13 +19,78 @@
 
 package org.elasticsearch.action.get;
 
+import org.elasticsearch.common.ParsingException;
+import org.elasticsearch.common.xcontent.XContentBuilder;
 import org.elasticsearch.common.xcontent.XContentFactory;
 import org.elasticsearch.common.xcontent.XContentParser;
 import org.elasticsearch.search.fetch.subphase.FetchSourceContext;
 import org.elasticsearch.test.ESTestCase;
 
+import java.io.IOException;
+
+import static org.hamcrest.Matchers.containsString;
+
 public class MultiGetRequestTests extends ESTestCase {
 
+    public void testAddWithInvalidKey() throws IOException {
+        final XContentBuilder builder = XContentFactory.jsonBuilder();
+        builder.startObject();
+        {
+            builder.startArray("doc");
+            {
+                builder.startObject();
+                {
+                    builder.field("_type", "type");
+                    builder.field("_id", "1");
+                }
+                builder.endObject();
+            }
+            builder.endArray();
+        }
+        builder.endObject();
+        final XContentParser parser = createParser(builder);
+        final MultiGetRequest mgr = new MultiGetRequest();
+        final ParsingException e = expectThrows(
+                ParsingException.class,
+                () -> {
+                    final String defaultIndex = randomAsciiOfLength(5);
+                    final String defaultType = randomAsciiOfLength(3);
+                    final FetchSourceContext fetchSource = FetchSourceContext.FETCH_SOURCE;
+                    mgr.add(defaultIndex, defaultType, null, fetchSource, null, parser, true);
+                });
+        assertThat(
+                e.toString(),
+                containsString("unknown key [doc] for a START_ARRAY, expected [docs] or [ids]"));
+    }
+
+    public void testUnexpectedField() throws IOException {
+        final XContentBuilder builder = XContentFactory.jsonBuilder();
+        builder.startObject();
+        {
+            builder.startObject("docs");
+            {
+                builder.field("_type", "type");
+                builder.field("_id", "1");
+            }
+            builder.endObject();
+        }
+        builder.endObject();
+        final XContentParser parser = createParser(builder);
+        final MultiGetRequest mgr = new MultiGetRequest();
+        final ParsingException e = expectThrows(
+                ParsingException.class,
+                () -> {
+                    final String defaultIndex = randomAsciiOfLength(5);
+                    final String defaultType = randomAsciiOfLength(3);
+                    final FetchSourceContext fetchSource = FetchSourceContext.FETCH_SOURCE;
+                    mgr.add(defaultIndex, defaultType, null, fetchSource, null, parser, true);
+                });
+        assertThat(
+                e.toString(),
+                containsString(
+                        "unexpected token [START_OBJECT], expected [FIELD_NAME] or [START_ARRAY]"));
+    }
+
     public void testAddWithInvalidSourceValueIsRejected() throws Exception {
         String sourceValue = randomFrom("on", "off", "0", "1");
         XContentParser parser = createParser(XContentFactory.jsonBuilder()
diff --git a/rest-api-spec/src/main/resources/rest-api-spec/test/mget/12_non_existent_index.yaml b/rest-api-spec/src/main/resources/rest-api-spec/test/mget/12_non_existent_index.yaml
index fd0100b0d63..06234642250 100644
--- a/rest-api-spec/src/main/resources/rest-api-spec/test/mget/12_non_existent_index.yaml
+++ b/rest-api-spec/src/main/resources/rest-api-spec/test/mget/12_non_existent_index.yaml
@@ -21,7 +21,6 @@
   - do:
       mget:
         body:
-          index:  test_2
           docs:
             - { _index: test_1, _type: test, _id: 1}