Alabama junior Jonathan Allen is part of a Crimson Tide defensive line that has taken on a big leadership role as the team prepares for the national championship game against Clemson. 

Allen, who leads Alabama with 12.0 sacks, talked about the mindset he and his fellow defenders have inside the locker room.

"The way we feel is you're either with us or against us," Allen said. "And if you're against us, we have nothing to say to you. I hate to be like that, but it's a train and you either get on or get off."

And the defense has been backing up the message it sends off the field with dominant performances on it. In the College Football Playoff semifinal at the Cotton Bowl, Alabama sacked Michigan State four times and kept the Big Ten champions off the scoreboard.

Now the attention turns to the undefeated Clemson Tigers. With only one game left on the schedule and everything at stake, Allen said the team will approach this matchup the same way it has every week.

"We just do what we've been doing. You never want to play on emotions when things go right. That emotion can definitely be a negative factor so we just try to focus just on doing our job."

The Crimson Tide will leave for Arizona on Friday and the championship will be played on January 11.