As a boxer, Joe Guzman went undefeated in Sadr City.

The Eloy native knocked out one fellow soldier in 20 seconds at an intra-Army tournament meant to keep morale up while fighting in Iraq, and how hardcore is that?

The heavyweight was an All-Army boxing champion from 2005 to 2008 and the All-Armed Forces champ in 2005, 2007 and 2008. The year he didn’t win, he was the runner-up.

In a world filled with big, tough guys, Staff Sgt. Guzman was the biggest, and toughest.

For the next week, he’ll help prepare America’s boxers for the rest of the world.

Now a coach, corner man and trainer, the 32-year-old is part of the staff giving final instruction to the nine men and three women of Team USA in Colorado Springs, Colo.

Read more about Guzman in Thursday's Arizona Daily Star.