Only show the first paragraph of posts on a WordPress front page

first-paragraph-front-page.php

<?php

/*
Plugin Name: Front page first paragraph
Plugin URI: http://example.com/
Description: Only use the first paragraph of posts on the front page
Version: 1.0
Author: Evan Solomon
Author URI: http://evansolomon.me
*/

/**
 * Copyright (c) 2012 Evan Solomon.
 *
 * Released under the GPL license
 * http://www.opensource.org/licenses/gpl-license.php
 *
 * This is an add-on for WordPress
 * http://wordpress.org/
 *
 * **********************************************************************
 * This program is free software; you can redistribute it and/or modify
 * it under the terms of the GNU General Public License as published by
 * the Free Software Foundation; either version 2 of the License, or
 * (at your option) any later version.
 *
 * This program is distributed in the hope that it will be useful,
 * but WITHOUT ANY WARRANTY; without even the implied warranty of
 * MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE. See the
 * GNU General Public License for more details.
 * **********************************************************************
 */


function es_front_page_first_paragraph( $content ) {
	if ( ! is_home() )
		return $content;

	$regex = '/<p>(.*?)<\/p>/';
	preg_match( $regex, $content, $match );

	if ( ! $match )
		return $content;

	return $match[0];
}
// Run this after wpautop()
add_filter( 'the_content', 'es_front_page_first_paragraph', 20 );

Strange, but I have only shown the second paragraph, not the first. Just write three paragraphs + picture.
How to fix?