Ethan Zohn, the soccer player who became the third winner of Survivor during its Africa season, has since been an advocate for his charity Grassroot Soccer and a real-life survivor of CD-20 Hodgkin's lymphoma.

Now he will take to Twitter on behalf of Universal Sports Network as their official social media commentator at the Boston Marathon, the network confirmed on April 10. Zohn will tweet live from near the Boylston Street finish line (the race will air live at 8:30 am ET on April 21).

“Last year’s tragic events still weigh heavy on our hearts, and I know that this year’s Boston Marathon will continue the healing process and show that Boston is stronger than ever,” said Zohn in a statement.

Zohn ran in the 2013 Boston Marathon and was at Mile 22 when the bombings occurred. In 2012, he intended to run but had to be treated for a recurrence of his rare form of lymphoma. His friend and fellow reality TV veteran Ryan Sutter ran in his place.

I first met Ethan Zohn while in Panama covering Survivor All-Stars in 2003 and have reported on him alongside Mark Dagostino in the years following. I have known Ryan Sutter since he won Trista Rehn's heart on the Bachelorette. The first time I spoke to them together was when they raced in the 2010 New York Marathon. Read that story here. 

For 2014 Boston Marathon twitter updates, follow @EthanZohn and @UniversalSports.