diff --git a/src/wp-includes/rest-api/endpoints/class-wp-rest-posts-controller.php b/src/wp-includes/rest-api/endpoints/class-wp-rest-posts-controller.php
index 008124d582..85af10f5f6 100644
--- a/src/wp-includes/rest-api/endpoints/class-wp-rest-posts-controller.php
+++ b/src/wp-includes/rest-api/endpoints/class-wp-rest-posts-controller.php
@@ -653,6 +653,26 @@ class WP_REST_Posts_Controller extends WP_REST_Controller {
 
 		$prepared_post->post_type = $this->post_type;
 
+		if ( ! empty( $prepared_post->post_name )
+			&& ! empty( $prepared_post->post_status )
+			&& in_array( $prepared_post->post_status, array( 'draft', 'pending' ), true )
+		) {
+			/*
+			 * `wp_unique_post_slug()` returns the same
+			 * slug for 'draft' or 'pending' posts.
+			 *
+			 * To ensure that a unique slug is generated,
+			 * pass the post data with the 'publish' status.
+			 */
+			$prepared_post->post_name = wp_unique_post_slug(
+				$prepared_post->post_name,
+				$prepared_post->id,
+				'publish',
+				$prepared_post->post_type,
+				$prepared_post->post_parent
+			);
+		}
+
 		$post_id = wp_insert_post( wp_slash( (array) $prepared_post ), true, false );
 
 		if ( is_wp_error( $post_id ) ) {
@@ -834,6 +854,24 @@ class WP_REST_Posts_Controller extends WP_REST_Controller {
 			return $post;
 		}
 
+		if ( ! empty( $post->post_status ) ) {
+			$post_status = $post->post_status;
+		} else {
+			$post_status = $post_before->post_status;
+		}
+
+		/*
+		 * `wp_unique_post_slug()` returns the same
+		 * slug for 'draft' or 'pending' posts.
+		 *
+		 * To ensure that a unique slug is generated,
+		 * pass the post data with the 'publish' status.
+		 */
+		if ( ! empty( $post->post_name ) && in_array( $post_status, array( 'draft', 'pending' ), true ) ) {
+			$post_parent     = ! empty( $post->post_parent ) ? $post->post_parent : 0;
+			$post->post_name = wp_unique_post_slug( $post->post_name, $post->ID, 'publish', $post->post_type, $post_parent );
+		}
+
 		// Convert the post object to an array, otherwise wp_update_post() will expect non-escaped input.
 		$post_id = wp_update_post( wp_slash( (array) $post ), true, false );
 
diff --git a/tests/phpunit/tests/rest-api/rest-posts-controller.php b/tests/phpunit/tests/rest-api/rest-posts-controller.php
index 6655c774fc..6ff1edae3e 100644
--- a/tests/phpunit/tests/rest-api/rest-posts-controller.php
+++ b/tests/phpunit/tests/rest-api/rest-posts-controller.php
@@ -5236,6 +5236,47 @@ class WP_Test_REST_Posts_Controller extends WP_Test_REST_Post_Type_Controller_Te
 		$GLOBALS['wp_rest_server']->override_by_default = false;
 	}
 
+	/**
+	 * @ticket 52422
+	 *
+	 * @covers WP_REST_Request::create_item
+	 */
+	public function test_draft_post_do_not_have_the_same_slug_as_existing_post() {
+		wp_set_current_user( self::$editor_id );
+		$this->factory()->post->create( array( 'post_name' => 'sample-slug' ) );
+
+		$request = new WP_REST_Request( 'PUT', sprintf( '/wp/v2/posts/%d', self::$post_id ) );
+		$params  = $this->set_post_data(
+			array(
+				'status' => 'draft',
+				'slug'   => 'sample-slug',
+			)
+		);
+		$request->set_body_params( $params );
+		$response = rest_get_server()->dispatch( $request );
+
+		$new_data = $response->get_data();
+		$this->assertSame(
+			'sample-slug-2',
+			$new_data['slug'],
+			'The slug from the REST response did not match'
+		);
+
+		$post = get_post( $new_data['id'] );
+
+		$this->assertSame(
+			'draft',
+			$post->post_status,
+			'The post status is not draft'
+		);
+
+		$this->assertSame(
+			'sample-slug-2',
+			$post->post_name,
+			'The post slug was not set to "sample-slug-2"'
+		);
+	}
+
 	public function tear_down() {
 		if ( isset( $this->attachment_id ) ) {
 			$this->remove_added_uploads();