Drupal 7: How to create dynamic link based upon url
Your code is fine except for a detail. The correct menu definition is the following one.

$items['%/page'] = array(
  'title' =&gt; 'Coach Page',
  'page callback' =&gt; 'coachpagelink',
  'page arguments' =&gt; array(0),  // Use an integer, not a string.
  'access arguments' =&gt; array('access content'),
  'type' =&gt; MENU_NORMAL_ITEM,
  'menu_name'=&gt;"menu-coach-menu",
);


If you use a string in the page arguments, the page callback is not receiving part of the URL, but that string. In your case, the page callback is always receiving '0' as argument, even when the page callback is invoked for example.com/jhondoe/page.