diff --git a/hibernate-reactive-core/src/main/java/org/hibernate/reactive/logging/impl/Log.java b/hibernate-reactive-core/src/main/java/org/hibernate/reactive/logging/impl/Log.java
index d3aa642786..eeec4ef9df 100644
--- a/hibernate-reactive-core/src/main/java/org/hibernate/reactive/logging/impl/Log.java
+++ b/hibernate-reactive-core/src/main/java/org/hibernate/reactive/logging/impl/Log.java
@@ -104,8 +104,8 @@ public interface Log extends BasicLogger {
 	@Message(id = 34, value = "The database returned no natively generated identity value")
 	HibernateException noNativelyGeneratedValueReturned();
 
-	@Message(id = 35, value = "The database can only generate identifiers of type Long")
-	HibernateException nativelyGeneratedValueMustBeLong();
+	@Message(id = 35, value = "The database can only generate identifiers of type Long: the id %1$d cannot be cast to %2$s ")
+	HibernateException nativelyGeneratedValueMustBeLong(Long id, @FormatWith(ClassFormatter.class) Class<?> idClass);
 
 	@Message(id = 356, value = "Wrong entity type!")
 	HibernateException wrongEntityType();
diff --git a/hibernate-reactive-core/src/main/java/org/hibernate/reactive/persister/entity/impl/ReactiveAbstractEntityPersister.java b/hibernate-reactive-core/src/main/java/org/hibernate/reactive/persister/entity/impl/ReactiveAbstractEntityPersister.java
index 6d094e443c..05420138ec 100644
--- a/hibernate-reactive-core/src/main/java/org/hibernate/reactive/persister/entity/impl/ReactiveAbstractEntityPersister.java
+++ b/hibernate-reactive-core/src/main/java/org/hibernate/reactive/persister/entity/impl/ReactiveAbstractEntityPersister.java
@@ -393,11 +393,6 @@ default CompletionStage<Serializable> insertReactive(
 		} );
 
 		Class<?> idClass = delegate().getIdentifierType().getReturnedClass();
-		if ( idClass.equals(Integer.class) || idClass.equals(Short.class) ) {
-			// since on MySQL we can only retrieve Long values, adjust to Long
-			// id will be cast back to the right type by castToIdentifierType()
-			idClass = Long.class;
-		}
 		return getReactiveConnection( session )
 				//Note: in ORM core there are other ways to fetch the generated identity:
 				//      getGeneratedKeys(), or an extra round select statement. But we
diff --git a/hibernate-reactive-core/src/main/java/org/hibernate/reactive/pool/impl/SqlClientConnection.java b/hibernate-reactive-core/src/main/java/org/hibernate/reactive/pool/impl/SqlClientConnection.java
index e5108d7239..12e17a2a3c 100644
--- a/hibernate-reactive-core/src/main/java/org/hibernate/reactive/pool/impl/SqlClientConnection.java
+++ b/hibernate-reactive-core/src/main/java/org/hibernate/reactive/pool/impl/SqlClientConnection.java
@@ -309,10 +309,19 @@ public CompletionStage<Void> close() {
 	private static <T> T getLastInsertedId(RowSet<Row> rows, Class<T> idClass, String idColumnName) {
 		final Long mySqlId = rows.property( MYSQL_LAST_INSERTED_ID );
 		if ( mySqlId != null ) {
+			// MySQL will return a Long for any of these types
 			if ( Long.class.equals( idClass ) ) {
 				return (T) mySqlId;
 			}
-			throw LOG.nativelyGeneratedValueMustBeLong();
+			if ( Integer.class.equals( idClass )
+					&& mySqlId <= Integer.MAX_VALUE ) {
+				return (T) mySqlId;
+			}
+			if ( Short.class.equals( idClass )
+					&& mySqlId <= Short.MAX_VALUE) {
+				return (T) mySqlId;
+			}
+			throw LOG.nativelyGeneratedValueMustBeLong( mySqlId, idClass );
 		}
 		final Row oracleKeys = rows.property( ORACLE_GENERATED_KEYS );
 		if ( oracleKeys != null ) {