Merriman missed the exhibition opener last Saturday against Chicago because he ended his holdout just a day earlier.
Inside linebacker Brandon Siler (ankle), offensive lineman Scott Mruczkowski (ankle), tight end Richie Brockel (shoulder) and left tackle Nick Richmond (knee) won't play, and it's unlikely offensive lineman Tyronne Green (ankle) will play.
The Chargers practiced Friday morning at Marine Corps Air Station Miramar. The team signed autographs and ran drills for an estimated 500 military members and their families.
"It's huge because they do so much for us as a country," said linebacker Larry English. "It's great for us to get a chance to come out and give back and show our support."
The Chargers spent time after practice signing autographs and chatting with the warriors. In the minds of the players, this is the least they can do to say thanks for the sacrifices Marines make.
"What these guys do for us is outstanding," said offensive guard Kris Dielman. "It's just a great way for us to come out here and show how much we appreciate it and that we're behind them and we hope everyone gets home safe."
As for the Marines themselves? They appreciate the opportunity to get to know some of the athletes they watch on TV.
"Everybody is really grateful," said Sergeant Charles Odom. "I mean, we do work really hard here and for them to notice every single year is really nice."
The highlight of the session came at the expense of the rookie class, which went through a pushup exercise while being yelled at by drill sergeants.