function LinkReplacer($text, $link, $new_text)
{
	$quoted_link = preg_quote($link,'/\'');
	$regexp = '/<a [^<]*href=["|\']?'.$quoted_link.'["|\']?[^>]*>.*<\\/a>/ui';
	$text=preg_replace($regexp, $new_text, $text);
	return $text;
}

function LinkReplacer($text, $link)
{
	$quoted_link = preg_quote($link,'/\'');
	$regexp = '/<a [^<]*href=["|\']?'.$quoted_link.'["|\']?[^>]*>.*<\\/a>/ui';
	$text=preg_replace($regexp,"REPLACE TEXT",$text);
	return $text;
}

$text=preg_replace('/<a [^<]*href=["|\']?([^ "\']*)["|\']?[^>].*>([^<]*)<\/a>/ui',' <a href="/">Здесь была оригинальная ссылка</a> ',$text);

Affects <A> tags for links starting with $link
Example: LinkReplacer ($text, 'http://www.snipplr.com') affects to
<a href="http://www.snipplr.com">Snipplr</a>
and <a href="http://www.snipplr.com/blog">Snipplr Blog</a>

Replace specified link tag in text

url, replace

PHP