Schema.org itemprop="url" inside anchor object (link)
So after spending some more time on the matter, I finally found the solution and I am posting it here in case anyone is interested.

Simply put the following code in your template.php file, inside your theme folder:

function YOUR-THEME_link($variables) {
  return '&lt;a itemprop="url" href="' . check_plain(url($variables['path'], $variables['options'])) . '"' . drupal_attributes($variables['options']['attributes']) . '&gt;&lt;span itemprop="title"&gt;' . ($variables['options']['html'] ? $variables['text'] : check_plain($variables['text'])) . '&lt;/span&gt;&lt;/a&gt;';
}


Hope that helps..
Remember to change 'YOUR-THEME' to your theme's name, and don't forget to clear the cache.