After undefeated Oklahoma State was upset by Iowa State on Friday night, the BCS floodgates were opened.

Top-five teams Oregon and Oklahoma now have more than a puncher's chance of reaching the BCS National Championship. But to get there, they'll have to pass stiff tests from fellow top-25 teams this weekend.

No. 18 USC at No. 4 Oregon

Carr-Crawford: Oregon 42, USC 31 - Despite USC's sanctions, this game will have huge consequences on a national scale. If Oregon wins this game, it can make serious claim to being the best one-loss team in the nation. However, this will be the Ducks' biggest test of the season.

USC is currently playing at a level reminiscent of the Pete Carroll days. The offense is clicking with QB Matt Barkley being aided by an emergent running game, and the defense is keeping opponents out of the end zone. Whether this trend can continue in Autzen Stadium, generally regarded as the most hostile venue in the conference, is debatable, but expect USC to at least give Oregon its most serious scare of the season. 

Fitch: Oregon - After the Ducks' impressive win against Stanford last week, it will be a challenge for the Trojans to beat Oregon, especially in Eugene. Oregon's running game is extremely powerful, and though USC's defense played extremely well against Stanford, they will be tested with the Ducks' explosive offense.

Shamout: Oregon 40, USC 38 - The key to this game for the Trojans will not be Matt Barkley. Instead, the performances of running backs Curtis McNeal and Marc Tyler, along with the offensive line, will be crucial to USC's success in Eugene on Saturday. If the Trojans can get their running game going and keep Oregon's potent 1-2-3 combo of LaMichael James, Darron Thomas and DeAnthony Thomas off the field, then they will be competitive. However, Trojans WR Robert Woods is still not 100 percent, and could see only limited playing time. Oregon narrowly wins a close battle at home.

No. 17 Nebraska at No. 20 Michigan

Carr-Crawford: Michigan 27, Nebraska 21 - This game is pivotal for Nebraska's Big Ten title hopes; Michigan, while sporting a good record, is pretty much out of the running for the title and is hoping to play spoiler. Both teams run a similar offensive attack, but Michigan's is much more diversified. While being bottled up as of late, QB Denard Robinson truly is college football’s more electrifying running quarterback.

Expect him to take full advantage of his talent against a Nebraska defense that has been mediocre for most of the season. Both teams are inconsistent through the air, but Nebraska QB Taylor Martinez has been solid of late, throwing just one pick in his last four games. Expect a competitive game, with Michigan coming through in the end.

Fitch: Nebraska - The Cornhuskers are coming off of a good win against Penn State and are bound to show some promise against the traditional Big Ten power Michigan. This will ultimately be a test of quarterbacks and how well each one can manage to control the ball and stay awake from making mental mistakes.

Shamout: Michigan 21, Nebraska 17 - Michigan QB Denard Robinson has almost 200 more rushing yards this year for the Wolverines than the second player on the list, RB Fitzgerald Toussaint. It's a good thing Robinson is so good running the ball, because his 13 interceptions don't speak too highly of his passing. The Wolverines' defense is formidable though, and should be able to contain Nebraska's running game led by RB Rex Burkhead, and bolstered by QB Taylor Martinez, who is not afraid to carry the ball himself. With two similar offenses, I'll take Michigan's D as the deciding factor in this one.

No. 5 Oklahoma at No. 25 Baylor

Carr-Crawford: Oklahoma 49, Baylor 28 - While both teams possess outstanding quarterbacks in Landry Jones and Robert Griffin III, don't expect this one to be close. Baylor's defense is a sieve, particularly against the pass. Despite losing NCAA career receptions leader Ryan Broyles to a torn ACL, Oklahoma's passing attack has remained potent. Baylor's only hope in keeping this game close is its own explosive offense, headed by Griffin, but the opportunistic defense of the Sooners should be capable of shutting it down. 

Fitch: Oklahoma - A true test between Baylor QB Robert Griffin, a candidate for the Heisman trophy, and OU's Landry Jones will be sure to provide a show on gameday. Both are exciting quarterbacks to watch, and with Oklahoma having one of the strongest defenses in the nation, it will prove to be an interesting matchup as Oklahoma tries to keep their hopes alive for the Big 12 championship.

Shamout: Oklahoma 54, Baylor 34 - The biggest question mark going into this matchup: will the Sooners and Bears be able to hit the combined 100-point mark. Who knows? Maybe Landry Jones and the Sooners will be able score 100 all by themselves against Baylor's 108th-ranked defense. Oklahoma will miss WR Ryan Broyles, whose college career ended two-weeks ago when he tore his ACL. But they'll miss him even more against Oklahoma State on Dec. 3.

No. 16 Kansas State at Texas

Carr-Crawford: Kansas State 30, Texas 17 - In any other year, this game wouldn’t be paid any attention, as Texas is given the benefit of the doubt due to its reputation. However, Kansas State actually leads its series with Texas at 6-5 overall, and Texas is not the same team it usually is. Behind the prolific running and accurate passing of QB Collin Klein, Kansas State has made a return to national relevance in just two years under coach Bill Snyder. The defense is among one of the nation’s best, despite being taken to triple overtime against Texas A&M last weekend.

Texas, despite sporting blue-chip athletes on both sides of the ball, still is not a big factor in the Big 12 race. It probably won't be until young QBs Case McCoy and David Ash mature and gain total command of the offense. While Texas will be able to slow Klein, they won't stop him completely, and their young offense will not have enough firepower to pick up the slack.

Fitch: Kansas State - The Wildcats has managed to impress with only two losses this season and the persistence of their quarterback Collin Klein. He leads the FBS with 34 total touchdowns (24 rushing, 10 passing). Klein will overmatch for the Texas defense and be the factor in giving Kansas State the win.

Shamout: Kansas State 31, Texas 13 - The Longhorns' greatest strength this season has been their running game, but that has taken a huge hit over the past two weeks. RB Fozzy Whittaker tore ligaments in his knee last week against Missouri and is now out for the year, while RBs Malcolm Brown and Jerome Bergeron are also banged up and might not play Saturday. Texas head coach Mack Brown will need a big performance from quarterback David Ash if the Longhorns hope to compete with Kansas State and their multi-tasking QB Collin Klein, who has over 1,500 yards passing, and over 1,000 yards rushing this season. Not too shabby.

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