Cam Newton, the No. 1 overall pick in April's NFL draft, will likely be the first quarterback off the bench.
That's not a big surprise considering Clausen has been getting all of the reps with the first-team offense during training camp.
"It's going to be a good test for us," Clausen said Friday morning. "We have to come out of the box fast and put some points on the board and keep progressing like we've been doing every day."
There's a good chance Newton will start at some point in the preseason, possibly as soon as next week against the Miami Dolphins.
Rivera said earlier in the week he wants to give both of his young quarterbacks a chance to run with the first team before making a decision on who will start the team's Sept. 11 regular season opener on the road against the Arizona Cardinals.
Rivera "told both me and Cam that he's going to play the best guy out there," Clausen said. "Myself and Cam have had ups and downs throughout camp and we're still learning. We're still young and I think (Saturday) is another big test. I can't wait to get out there."
Although Clausen and Newton have formed a friendship, they're still competing for the No. 1 spot.
But Clausen said that isn't something he's thinking about.
"You can't think about that when you're going and playing," Clausen said. "You just have to go out and play ball and keep doing the things you are doing in practice, getting in and out of the huddle, get to the line of scrimmage and at the end of the day make some plays."
"It's a different philosophy and we're going to be stretching the field more," Clausen said. "We have a lot of weapons now. It's going to be fun. It's been a lot of fun this training camp."
Copyright 2011 by The Associated Press