The Dallas Cowboys were issued a 15-yard unsportsmanlike conduct penalty after forcing a fumble on Indianapolis Colts running back Jonathan Taylor during Sunday's Week 9 win.

The penalty came after linebacker DeMarvion Overshown, who was inactive and in street clothes with hamstring and back injuries, ran out onto the field to celebrate with his defensive teammates.

This behavior sparked controversy and questions about the team's culture under head coach Brian Schottenheimer.

When speaking to reporters on Thursday, Overshown said he apologized to his teammates and admitted that he didn't know he was breaking any rules.

“I really didn’t know the rule until I heard Dee Winters, he yelled, ‘D-Mo, you can’t be out here!’ That’s when I looked back and I already saw the ref pointing," Overshown said, via team reporter Nick Harris. "I was just like, I’ll take the butt chewing that I’ll get. It won’t happen again, and I apologized to the team.”

“I was just caught in the moment," he added. "It’s just a lesson learned. It’s not going to change how passionate I am about my teammates when they make big plays. It’s not an indictment on [Schottenheimer]. It’s on me as a player. I own it.”

Overshown returned to practice in a limited capacity on Wednesday, and was upgraded to full participation on Thursday. The 26-year-old linebacker said he expects to take the field for Sunday's Week 10 matchup against the San Francisco 49ers.

Sunday's game will kick off at 4:25 p.m. ET.