How to use next_post tag in index.php rather than post_nav_link

Hello everyone,

I want my blog to display only one post per page. And under, the post, I’d like navigation links that display the next/previous post title.

It looks like this is possible for the single.php which uses the next_post tag in the loop, but not for the index page which uses the post_nav_link tag.

Do you know what I should change if I want the next_post tag also in the index.php.

Thanks for your help !
Julien