Wordpress Disqus - If have comments, else... issue

Wordpress Disqus - If have comments, else... issue

I'd like to hide the wordpress comment count if there are no comments on
the specific post.
<?php
if (have_comments()) {
echo comments_number('');
} else {
echo ' ';
}
?>
This works fine with the standard Wordpress comments but doesn't work when
Disqus is installed.
Does anybody know a work around?