diff --git a/core/modules/link/src/Plugin/Field/FieldType/LinkItem.php b/core/modules/link/src/Plugin/Field/FieldType/LinkItem.php
index a552a0e..4c0467c 100644
--- a/core/modules/link/src/Plugin/Field/FieldType/LinkItem.php
+++ b/core/modules/link/src/Plugin/Field/FieldType/LinkItem.php
@@ -177,11 +177,21 @@ public function getUrl() {
    * {@inheritdoc}
    */
   public function setValue($values, $notify = TRUE) {
+    // Treat the values as property value of the main property, if no array is
+    // given.
+    if (isset($values) && !is_array($values)) {
+      $values = [static::mainPropertyName() => $values];
+    }
+    if (isset($values)) {
+      $values += [
+        'options' => [],
+      ];
+    }
     // Unserialize the values.
     // @todo The storage controller should take care of this, see
     //   SqlContentEntityStorage::loadFieldItems, see
     //   https://www.drupal.org/node/2414835
-    if (isset($values['options']) && is_string($values['options'])) {
+    if (is_string($values['options'])) {
       $values['options'] = unserialize($values['options']);
     }
     parent::setValue($values, $notify);
diff --git a/core/modules/link/src/Tests/LinkItemTest.php b/core/modules/link/src/Tests/LinkItemTest.php
index 8431757..a476853 100644
--- a/core/modules/link/src/Tests/LinkItemTest.php
+++ b/core/modules/link/src/Tests/LinkItemTest.php
@@ -101,6 +101,36 @@ public function testLinkItem() {
     $this->assertEqual($entity->field_test->title, $new_title);
     $this->assertEqual($entity->field_test->options['attributes']['class'], $new_class);
 
+    // Check that if we only set uri the default values for title and options
+    // are also initialized.
+    $entity->field_test = ['uri' => 'internal:/node/add'];
+    $this->assertEqual($entity->field_test->uri, 'internal:/node/add');
+    $this->assertNull($entity->field_test->title);
+    $this->assertIdentical($entity->field_test->options, []);
+
+    // Check that if set uri and serialize options then the default values are
+    // properly initialized.
+    $entity->field_test = [
+      'uri' => 'internal:/node/add',
+      'options' => serialize(['query' => NULL]),
+    ];
+    $this->assertEqual($entity->field_test->uri, 'internal:/node/add');
+    $this->assertNull($entity->field_test->title);
+    $this->assertNull($entity->field_test->options['query']);
+
+    // Check that if we set the direct value of link field it correctly set the
+    // uri and the default values of the field.
+    $entity->field_test = 'internal:/node/add';
+    $this->assertEqual($entity->field_test->uri, 'internal:/node/add');
+    $this->assertNull($entity->field_test->title);
+    $this->assertIdentical($entity->field_test->options, []);
+
+    // Check that setting LinkItem value NULL doesn't generate any error or
+    // warning.
+    $entity->field_test[0] = NULL;
+    $this->assertNull($entity->field_test[0]->getValue());
+
+
     // Test the generateSampleValue() method.
     $entity = entity_create('entity_test');
     $entity->field_test->generateSampleItems();