Using ESPN's developer API's, you can query for news on a specific athlete using the 'athleteId'. See the Methods section of their docs:
http://developer.espn.com/docs/headlines#parameters
If you look up a player profile you can find the athlete id in the url of the page, but my question is how can we find this id using solely the APIs? With just the athlete's name?
If you go to a team's roster page, use inspect element, or whatever equivalent for the browser you use, and look at the table element of all the players on the team. Within the 'td' tags, you'll find a player ID. You could scrape the screen, store all of the player ids locally, and then use them as parameters in your api calls. This is merely a suggestion, but it should work, if the id that is used on the page is the same as the id needed to get that player's information in api.