Joomla Article - How to Stop Google bot to Index a Duplicate Page?

My site is in Joomla. I have Few articles which are relevant to appear in more than one section. So i want to block one or more articles from bot to avoid duplicate content.

There is an option in Joomla. While adding article i can set metadata information.

I have set Robots : nofollow for the duplicate articles.

I guess i have made it wrong because Duplicate title tags and Meta Descriptions is increasing rapidly in webmaster tools-.

Please can anyone help me . I have to remove those errors in webmaster tools also i don’t want bot to crawl my duplicate articles.

A better way to organise your site is to have each article there only once, and then have all links pointing to that one copy of the article. That will avoid the problem of duplicate content, as well as making it easier for visitors to the site, and hopefully for you to manage the site as well.

Why worry about it, if the article(s) is being indexed then you don’t have to worry about the bot getting caught in an infinite loop and if Google realise it’s dup content they’ll de-index it on their own anyway and just let one version of it rank. Right now you’re enjoying an article being indexed more than it should giving you more opportunities to get traffic, why is that a problem?

Have you tried a plugin like Ninjabot? -

How would you achieve that with Joomla?