There was much commentary during the Rose Bowl about Oregon's defensive strategy in the game. Quarterback Jameis Winston was Florida State's most potent offensive weapon. Especially with the absence of cornerback Ifo Ekpre-Olomu, it seemed like Oregon's big weakness would be the secondary, and that the Seminoles could exploit the Ducks in the passing game. Oregon's counter to this was classic bend-but-don't-break defense. Form an umbrella with your defensive secondary, keep everything in front of you, and don't give up a big play. Give up short stuff, force the offense to make a drive, and hold them to field goals when space becomes an issue in the red zone.
This strategy worked out brilliantly for the Ducks in the Rose Bowl. As they knew they would, Oregon gave up yards--528 of them, and 348 through the air--but they held FSU to field goals on a couple of drives, got a goal line stand, and were beneficiaries as the Seminoles coughed up the ball five times. The Ducks gave up some rushing yards, and some passes over the middle, but were largely effective in their game plan.
Unfortunately, the Ducks have to do everything different in the National Championship Game.
Ohio State is a very different beast than Florida State. For one, you can't count on them to leave the ball all over the field like the Seminoles did. FSU was a sloppy, turnover prone mess the entire season. The Buckeyes have been anything but. Secondly, it's not the Ohio State quarterback you have to fear, but its running game.
Much has been made about Cardale Jones. He's been impressive in two wins against Wisconsin and Alabama. And it's also misleading to call him a third stringer--he's been getting second team reps all year. He throws a beautiful deep ball, and Ohio State will take some shots downfield. But Jones has also looked erratic at times. He has struggled with accuracy. He has thrown interceptions. He's thrown balls into the stands. He's not going to be asked to pick apart a defense like Winston was. Oftentimes, Jones will be asked to make one read and take off running.
It's that run threat that makes the Buckeyes so dangerous. Running back Ezekiel Elliott rushed for 230 yards and 11.5 yards per carry on the Alabama defense. Jones has proven to be a dangerous runner, the equivalent of a large power back that is difficult to bring down. Ohio State didn't beat Alabama due to Jones' passing, which was mediocre at best. They won because Alabama couldn't stop their running game and get off the field.
Which is why Oregon has to approach this game differently than they did the Rose Bowl. Ohio State wants to take the ball out of Cardale Jones' hands as much as possible and let that running game take them down the field. Elliott is their most dangerous weapon, and the ball in his hands keeps the Oregon offense on the sideline. Meanwhile, while Jones has made some great plays, he's shown to be shaky in reading coverages, and hasn't show that he can make an opposing team pay for sending a blitz. In fact, he's been somewhat of a one-trick pony in the passing game, with go routes down the sidelines accounting for most of his shots downfield. Most of his passes have been checkdowns. He's simply not proficient enough at this point to attack the field middle-deep.
Oregon has to slow down the Ohio State running game. Every time they can get the Buckeyes in a third and long, they are forcing Ohio State to use their weakest link, which is still Jones and the passing game. Blitz the kid, disguise the coverages, and force him into a mistake. Three of Ohio State's touchdowns came on an 85-yard TD run, a reverse pass, and an interception return. The Buckeyes scored 42 points because Cardale Jones wasn't forced to carry them.
You're not going to shut down the Buckeye running game. If you're Oregon, you just have to get enough stops to outscore them. FSU wanted to put the game in the hands of the quarterback. Ohio State doesn't.