To Nick Newell, it's an afterthought most days.
Newell, a 27-year-old mixed martial arts fighter with an undeveloped left arm, took the time at the close of training to visit military veteran amputees in Camp Pendleton who are part of the group "Operation Warrior Reconnect."
"What they've done is way more fantastic, more brave, than anything I've ever done," Newell said. "Sacrificing your life for our country, that's something."
But what Newell, a native of New England, saw back in the Marines' eyes gave him pause: Their appreciation of him.
"Those guys have lost limbs too, or had significant damage to them," Newell said. "I think all of us knew even if the odds are against you, you can accomplish things."
Newell, who won more than 300 wrestling matches in high school and his small college, is 9-0 while fighting with the birth condition known as a congenital amputation, which caused his left arm's growth to be stopped just past the elbow.
Saturday, on the undercard of the NBC Sports Network-televised World Series of Fighting at Citizens Business Bank Arena in Ontario, Newell will fight Keon Caldwell (9-1, nine knockouts) with the winner getting invited to a four-fighter tournament for the WSOF 155-pound belt.
"It's a tough, dangerous fight," Newell said. "He's a talented competitor. But I got in this to test myself, not to get any favors."
Newell, asked to identify his strengths, said, "My ability to mix it up, to keep people guessing.
"And my heart.
"I don't care when people ask about my arm. I'm asked about it in every interview. I have my answers. Look, I've been through this my whole life. And I love my life."
Saturday's fight card includes a main-event battle between Angel De Anda and Tyrone Spong, a gifted kick boxer-striker trained by Miguel Cotto's former trainer, Pedro Diaz.
Tickets remain on sale, priced at $29-$199, with special pricing for members of the military.