diff --git a/spring-data-mongodb/src/main/java/org/springframework/data/mongodb/core/EntityOperations.java b/spring-data-mongodb/src/main/java/org/springframework/data/mongodb/core/EntityOperations.java
index a9b1d19d8..1ccd16023 100644
--- a/spring-data-mongodb/src/main/java/org/springframework/data/mongodb/core/EntityOperations.java
+++ b/spring-data-mongodb/src/main/java/org/springframework/data/mongodb/core/EntityOperations.java
@@ -47,6 +47,7 @@ import com.mongodb.util.JSONParseException;
  * Common operations performed on an entity in the context of it's mapping metadata.
  * 
  * @author Oliver Gierke
+ * @author Mark Paluch
  * @since 2.1
  * @see MongoTemplate
  * @see ReactiveMongoTemplate
@@ -70,11 +71,11 @@ class EntityOperations {
 		Assert.notNull(entity, "Bean must not be null!");
 
 		if (entity instanceof String) {
-			return new SimpleEntity(parse(entity.toString()));
+			return new UnmappedEntity(parse(entity.toString()));
 		}
 
 		if (entity instanceof Map) {
-			return new SimpleEntity((Map<String, Object>) entity);
+			return new SimpleMappedEntity((Map<String, Object>) entity);
 		}
 
 		return MappedEntity.of(entity, context);
@@ -94,11 +95,11 @@ class EntityOperations {
 		Assert.notNull(conversionService, "ConversionService must not be null!");
 
 		if (entity instanceof String) {
-			return new SimpleEntity(parse(entity.toString()));
+			return new UnmappedEntity(parse(entity.toString()));
 		}
 
 		if (entity instanceof Map) {
-			return new SimpleEntity((Map<String, Object>) entity);
+			return new SimpleMappedEntity((Map<String, Object>) entity);
 		}
 
 		return AdaptibleMappedEntity.of(entity, context, conversionService);
@@ -286,7 +287,7 @@ class EntityOperations {
 	}
 
 	@RequiredArgsConstructor
-	private static class SimpleEntity<T extends Map<String, Object>> implements AdaptibleEntity<T> {
+	private static class UnmappedEntity<T extends Map<String, Object>> implements AdaptibleEntity<T> {
 
 		private final T map;
 
@@ -388,6 +389,31 @@ class EntityOperations {
 		}
 	}
 
+	private static class SimpleMappedEntity<T extends Map<String, Object>> extends UnmappedEntity<T> {
+
+		public SimpleMappedEntity(T map) {
+			super(map);
+		}
+
+		/*
+		 * (non-Javadoc)
+		 * @see org.springframework.data.mongodb.core.EntityOperations.PersistableSource#toMappedDocument(org.springframework.data.mongodb.core.convert.MongoWriter)
+		 */
+		@Override
+		@SuppressWarnings("unchecked")
+		public MappedDocument toMappedDocument(MongoWriter<? super T> writer) {
+
+			T bean = getBean();
+			bean = (T) (bean instanceof Document //
+					? (Document) bean //
+					: new Document(bean));
+			Document document = new Document();
+			writer.write(bean, document);
+
+			return MappedDocument.of(document);
+		}
+	}
+
 	@RequiredArgsConstructor(access = AccessLevel.PROTECTED)
 	private static class MappedEntity<T> implements Entity<T> {
 
diff --git a/spring-data-mongodb/src/test/java/org/springframework/data/mongodb/core/MongoTemplateTests.java b/spring-data-mongodb/src/test/java/org/springframework/data/mongodb/core/MongoTemplateTests.java
index d2c869638..93dd66e08 100644
--- a/spring-data-mongodb/src/test/java/org/springframework/data/mongodb/core/MongoTemplateTests.java
+++ b/spring-data-mongodb/src/test/java/org/springframework/data/mongodb/core/MongoTemplateTests.java
@@ -26,6 +26,8 @@ import static org.springframework.data.mongodb.core.query.Criteria.*;
 import static org.springframework.data.mongodb.core.query.Query.*;
 import static org.springframework.data.mongodb.core.query.Update.*;
 
+import com.mongodb.BasicDBObject;
+import com.mongodb.DBObject;
 import lombok.AllArgsConstructor;
 import lombok.Data;
 import lombok.EqualsAndHashCode;
@@ -36,11 +38,13 @@ import lombok.experimental.Wither;
 import java.lang.reflect.InvocationTargetException;
 import java.math.BigDecimal;
 import java.math.BigInteger;
+import java.time.Duration;
 import java.time.Instant;
 import java.util.*;
 import java.util.stream.Collectors;
 import java.util.stream.IntStream;
 
+import org.bson.Document;
 import org.bson.types.ObjectId;
 import org.hamcrest.collection.IsMapContaining;
 import org.joda.time.DateTime;
@@ -2061,6 +2065,18 @@ public class MongoTemplateTests {
 		assertThat(result.get(0).field, is(value));
 	}
 
+	@Test // DATAMONGO-2028
+	public void allowInsertOfDbObjectWithMappedTypes() {
+
+		DBObject dbObject = new BasicDBObject("_id", "foo").append("duration", Duration.ofSeconds(100));
+		template.insert(dbObject, "sample");
+		List<org.bson.Document> result = template.findAll(org.bson.Document.class, "sample");
+
+		assertThat(result.size(), is(1));
+		assertThat(result.get(0).getString("_id"), is("foo"));
+		assertThat(result.get(0).getString("duration"), is("PT1M40S"));
+	}
+
 	@Test // DATAMONGO-816
 	public void shouldExecuteQueryShouldMapQueryBeforeQueryExecution() {