diff --git a/src/wp-includes/rest-api/endpoints/class-wp-rest-autosaves-controller.php b/src/wp-includes/rest-api/endpoints/class-wp-rest-autosaves-controller.php
index f99a201974..e5409e7329 100644
--- a/src/wp-includes/rest-api/endpoints/class-wp-rest-autosaves-controller.php
+++ b/src/wp-includes/rest-api/endpoints/class-wp-rest-autosaves-controller.php
@@ -360,35 +360,34 @@ class WP_REST_Autosaves_Controller extends WP_REST_Revisions_Controller {
 			return $post;
 		}
 
+		// Only create an autosave when it is different from the saved post.
+		$autosave_is_different = false;
+		$new_autosave          = _wp_post_revision_data( $post_data, true );
+
+		foreach ( array_intersect( array_keys( $new_autosave ), array_keys( _wp_post_revision_fields( $post ) ) ) as $field ) {
+			if ( normalize_whitespace( $new_autosave[ $field ] ) !== normalize_whitespace( $post->$field ) ) {
+				$autosave_is_different = true;
+				break;
+			}
+		}
+
+		if ( ! $autosave_is_different ) {
+			return new WP_Error(
+				'rest_autosave_no_changes',
+				__( 'There is nothing to save. The autosave and the post content are the same.' ),
+				array( 'status' => 400 )
+			);
+		}
+
 		$user_id = get_current_user_id();
 
 		// Store one autosave per author. If there is already an autosave, overwrite it.
 		$old_autosave = wp_get_post_autosave( $post_id, $user_id );
 
 		if ( $old_autosave ) {
-			$new_autosave                = _wp_post_revision_data( $post_data, true );
 			$new_autosave['ID']          = $old_autosave->ID;
 			$new_autosave['post_author'] = $user_id;
 
-			// If the new autosave has the same content as the post, delete the autosave.
-			$autosave_is_different = false;
-
-			foreach ( array_intersect( array_keys( $new_autosave ), array_keys( _wp_post_revision_fields( $post ) ) ) as $field ) {
-				if ( normalize_whitespace( $new_autosave[ $field ] ) !== normalize_whitespace( $post->$field ) ) {
-					$autosave_is_different = true;
-					break;
-				}
-			}
-
-			if ( ! $autosave_is_different ) {
-				wp_delete_post_revision( $old_autosave->ID );
-				return new WP_Error(
-					'rest_autosave_no_changes',
-					__( 'There is nothing to save. The autosave and the post content are the same.' ),
-					array( 'status' => 400 )
-				);
-			}
-
 			/** This filter is documented in wp-admin/post.php */
 			do_action( 'wp_creating_autosave', $new_autosave );
 
diff --git a/tests/phpunit/tests/rest-api/rest-autosaves-controller.php b/tests/phpunit/tests/rest-api/rest-autosaves-controller.php
index 088f02b67d..32ba9768e7 100644
--- a/tests/phpunit/tests/rest-api/rest-autosaves-controller.php
+++ b/tests/phpunit/tests/rest-api/rest-autosaves-controller.php
@@ -674,4 +674,38 @@ class WP_Test_REST_Autosaves_Controller extends WP_Test_REST_Post_Type_Controlle
 
 		wp_delete_post( $post_id );
 	}
+
+	/**
+	 * @ticket 49532
+	 *
+	 * @covers WP_REST_Autosaves_Controller::create_post_autosave
+	 */
+	public function test_rest_autosave_do_not_create_autosave_when_post_is_unchanged() {
+		// Create a post by the editor.
+		$post_data = array(
+			'post_content' => 'Test post content',
+			'post_title'   => 'Test post title',
+			'post_excerpt' => 'Test post excerpt',
+			'post_author'  => self::$editor_id,
+			'post_status'  => 'publish',
+		);
+		$post_id   = wp_insert_post( $post_data );
+
+		wp_set_current_user( self::$editor_id );
+
+		$autosave_data = array(
+			'post_content' => $post_data['post_content'],
+		);
+
+		// Create autosaves response.
+		$request = new WP_REST_Request( 'POST', '/wp/v2/posts/' . $post_id . '/autosaves' );
+		$request->add_header( 'content-type', 'application/json' );
+		$request->set_body( wp_json_encode( $autosave_data ) );
+
+		$response = rest_get_server()->dispatch( $request );
+		$data     = $response->get_data();
+
+		$this->assertSame( 400, $response->get_status(), 'Response status is not 400.' );
+		$this->assertSame( 'rest_autosave_no_changes', $data['code'], 'Response "code" is not "rest_autosave_no_changes"' );
+	}
 }