STATE COLLEGE, Pa. -- Call Navy one dimensional. Go on, call them predictable.

Penn State's players know what's coming. Everyone does. Navy's recipe for success hasn't been a recipe inasmuch as it's been a single ingredient: Run.

But knowing what's coming and knowing how to stop it are two very different challenges.

They're good at what they do, and they're fast," defensive end Pete Massaro said. "There's no way you can get a scout-team offense up to that level in just a few days."

Loading the box is one solution, but it's a lot like marking "C" on a Scantron test: It can't be the answer every time. With the triple option, Navy can roll around the outside if a defensive end bites. If the DBs hesitate, watch out for the play-action.

Through sleight-of-hand and a tricky set-up, Navy has ridden this offense to become one of the country's premier running teams. Since 2002, the Middies have consistently ranked as one of the nation's top four rushing teams.

Well, except for 2010. That was a down year. Navy finished just sixth nationally and rushed for a paltry 284.8 yards a game.

"You have to change up your whole defense for a team like Navy, Georgia Tech and any triple-option team," cornerback Adrian Amos said.

Bill O'Brien preached discipline this week like Navy preached ball-control. For Penn State to out-muscle a team that runs four times for every pass, their front-seven can't be out of position.

Quarterback Trey Miller will dive forward more often than he drops back. Noah Copeland and at least half-a-dozen other running backs will record a carry. O'Brien knows what to expect -- everybody does -- it's just a question of the outcome.

"I didn't schedule Navy," O'Brien said with a laugh.

Surprise tailback? O'Brien offered fans a bit of a riddle during his weekly radio show Thursday.

"We're going to do a few different things on Saturday," he said. "There' be one other guy back there that you haven't seen carrying the football."

O'Brien told fans they'd have to see Saturday who it was, but reporters and fans have already ventured quite a few guesses: Gerald Hodges, Paul Jones, Glenn Carson, P.J. Byers, Alex Kenney, Akeel Lynch, Garry Gilliam, etc.

Byers and Lynch are the favorites, but one can never tell with O'Brien -- who used a linebacker (Hodges) to return kicks during Game 1.

Leading the Big Ten: Even if sophomore wideout Allen Robinson fails to record a catch Saturday, he could still lead the conference in receptions.

He currently has 19 catches, while Purdue's O.J. Ross is second with 13 grabs. Robinson might have even had 21 catches -- if he didn't drop two on back-to-back plays last week.

"I had a couple drops this week because of lack of concentration," he said. "I just can't let that happen anymore. ... I need to focus and make sure I'm looking the ball in."

Where's Amos? O'Brien said in the preseason that Amos could play anywhere: safety, cornerback -- even linebacker.

Against a run-first offense like Navy, which requires some sure-tacklers, it'll be interesting to see where Amos lines up. If O'Brien wants to move Amos around in the early part of the season, this game seems like his best bet.

Stopping the run: Deion Barnes might be the team's best pass-rusher -- he's tied for the Big Ten lead in sacks with three -- but he admitted this week he needs to get better at stopping the run.

With the better run-stuffer, Massaro, likely out with several injuries, Navy could target the redshirt freshman.

"You got to read blocks better," Barnes said. "You have to be more attentive this week."

Trick plays: O'Brien was asked Thursday if he planned to use many trick plays against Navy, like last week's fake punt that resulted in a 19-yard scamper by a linebacker.

"We're going to pull out all the stops," he said. "So we got a few trick plays for Saturday, and we'll see if we can pull them out. When you call them, you want them to work."