Brent, out on bail after being charged with intoxication manslaughter resulting in the death of close friend and teammate Jerry Brown, said encouraging words to several of his teammates before the game.
During the national anthem, he had Brown's jersey draped over his shoulder before it was placed on the bench.
Brent then watched the game -- a 27-24 overtime win for the Cowboys -- on the sideline.
"We wanted him here, that's our brother," defensive end Jason Hatcher said. "He was very supportive. He was able to tell us what was going on, on the field, and he was there for us. He came in here and said, 'Don't feel sorry for me, ball.' That's the type of guy he is. He's a young guy who made a mistake, and at the end of the day, God has a purpose for his life."
Coach Jason Garrett said Brown's mother, Stacey Jackson, asked the team to support Brent as he grieves, and that being around the team should be considered a positive.
Hatcher said he's hoping Brent can come to Dallas' remaining regular-season games, next week against New Orleans and the finale against the Washington Redskins in Landover, Md.
"Our team and our players wanted him today on the sideline," Cowboys owner Jerry Jones said of Brent. "Jerry's mother (Stacey Jackson) asked us directly as a group. She said, 'Support him. Help him. He needs your help. Jerry wants that. I want that.'
"His teammates asked him to come and be down there with them, and that's where we are. I do know that certainly that there's the other side of the coin (where he shouldn't be there), but this is a case that the people that arguably he's the closest to (his teammates) really wanting him around for him."