Here's how SI.com's playoff works. Using the final BCS rankings, we seeded the top 16 teams in order. To avoid inter-conference matchups in the first round, we made two simple adjustments (swapping Arizona State and Florida in the seeding process, as well as Illinois and Boston College). For the purpose of this simulation, we are going to assume that all "banged up" players (Tim Tebow, Glenn Dorsey, etc.) will take part in the action. We will be crowning a champion tomorrow. So start voting and let your voice be heard.

Oklahoma and USC facing off in a title game -- sounds familiar. The Sooners and Trojans last played in the 2005 Orange Bowl (a.k.a. the BCS title game). But the much-anticipated battle of the unbeatens didn't quite play out as expected -- USC ran away with a 55-19 victory. In the first meeting between two Heisman Trophy winners, USC QB Matt Leinart outplayed Jason White. While Leinart threw for 332 yards and five touchdowns, White tossed three interceptions.

How will things play out this time around? Here are three reasons why each team should prevail.

Three reasons Oklahoma should win:

1. Oklahoma's more well-rounded. When OU is firing on all cylinders -- as it was during the Big 12 title game -- it may be the best team in America. While USC has faced notable struggles offensively, Oklahoma excels on both sides of the ball. The Sooners rank third nationally in scoring offense and ninth in scoring defense.

2. Allen Patrick is a man on a mission. Entering this year, Patrick was primed for a big season. But through the first 11 games of the season, he eclipsed 100 yards just once. Then, freshman RB DeMarco Murray suffered a season-ending injury against Texas Tech. While Murray's injury was a big blow to Oklahoma, it forced Patrick to take on a bigger role in the run game, and the senior has responded. Against Oklahoma State and Missouri (in the Big 12 championship), Patrick combined for 290 yards and four touchdowns. The Sooners must establish the run against USC, and the rejuvenated Patrick may be just the man to do it.

3. It's payback time. Ashlee Simpson may have been booed off the field following her '05 Orange Bowl halftime show, but even Simpson's humiliation paled in comparison to Oklahoma's. This debacle is still fresh in coach Bob Stoops' mind, and his team will be out for blood.

Three reasons USC should win:

1. Defense wins championships. It may sound cliché, but hey, this is a virtual playoff. While Oklahoma's defense is nothing to scoff at, the Trojans are far superior in this area. Playing in the high-flying Pac-10, USC ranked second in total defense (258.83 yards per game) and fourth in scoring defense (15.92 points per game). Oklahoma freshman QB Sam Bradford has never faced a challenge like this, as USC's defense is filled to the brim with future pros.

2. John David Booty's about-face. In the first five games of the season, Booty threw eight interceptions. But since his return from injury (a broken middle finger he suffered in a shocking loss to Stanford), the senior signal caller has led the Trojans to four straight wins by throwing eight touchdown passes to just one interception.

3. Pete Carroll's BCS bowl run. USC earned its sixth-consecutive BCS bowl bid this season. In the Trojans' previous five BCS appearances, they've gone 4-1, with each win coming by at least 14 points. Carroll's teams always seem to shine on a big stage. In comparison, Stoops owns a 2-3 mark in BCS games.

Who is your pick? Go ahead and cast your vote.

CLICK BELOW FOR RESULTS FROM PREVIOUS ROUNDS

No. 4 Oklahoma upsets No. 1 Ohio State: 68,234 (63 percent) to 39,980 (37 percent).

No. 7 USC defeats No. 11 Florida: 84,543 (63 percent) to 48,863 (37 percent).

No. 1 Ohio State defeats No. 9 West Virginia: 82,035 (53 percent) to 73,390 (47 percent).

No. 4 Oklahoma defeats No. 5 Georgia: 92,995 (53 percent) to 82,041 (47 percent).

No. 7 USC upsets No. 2 LSU: 123,982 (55 percent) to 101,200 (45 percent).

No. 11 Florida upsets No. 3 Virginia Tech: 125,479 (68 percent) to 58,363 (32 percent).

No. 1 Ohio State defeats No. 16 Tennessee: 136,283 (74 percent) to 47,751 (26 percent).

No. 2 LSU defeats No. 15 Clemson: 178,183 (93 percent) to 13,402 (seven percent).

No. 3 Virginia Tech defeats No. 14 Illinois: 129,160 (65 percent) to 70,678 (35 percent).

No. 4 Oklahoma defeats No. 13 Boston College: 174,327 (87 percent) to 27,819 (13 percent).

No. 5 Georgia defeats No. 12 Arizona State: 145,082 (84 percent) to 27,819 (16 percent).

No 11 Florida upsets No. 6 Missouri: 130,996 (70 percent) to 56,304 (30 percent).

No. 7 USC defeats No. 10 Hawaii: 140,157 (74 percent) to 50,217 (26 percent).

No. 9 West Virginia upsets No. 8 Kansas: 126,413 (68 percent) to 60,283 (32 percent).

SI Apps
We've Got Apps Too
Get expert analysis, unrivaled access, and the award-winning storytelling only SI can provide - from Peter King, Tom Verducci, Lee Jenkins, Seth Davis, and more - delivered straight to you, along with up-to-the-minute news and live scores.