USC and Oregon are still on a collision course for Nov. 3. Yet, both divisions appear to be much improved. And what's more interesting is the hierarchy shift in both the North and South that took place last week. Oregon State and Washington could be the top challengers in the North while Arizona State and UCLA look like the best bets to topple USC in the South. UCLA and Oregon State have must-win games this weekend, while Washington's season could be on the line in Eugene.

This league seems to get deeper and deeper each Saturday. After another stellar weekend of action out West, six Pac-12 schools now reside in the AP Top 25. Washington and UCLA slide into the rankings, while Arizona State is knocking on the door and Arizona is clearly another solid team. And as strange as it may sound, Cal might be the best 1-4 team in the nation.  

The 2012 season is turning into one of the best fans have seen out West in years and it has a chance to get even better. Oregon State and Arizona State made huge statements last week, but both have huge road tests this weekend that will prove if they belong in conference contention. Otherwise, all eyes across the college football world should be on the Pac-12 this Thursday evening.

Pac-12's Top Storylines to Watch in Week 5:

Oregon and USC used stellar defensive performances to get key home conference wins. Oregon State and Mike Riley shocked the country once again with an upset win over a ranked opponent — this time on the road — as the Beavers have added their name to the crowded North Division race. The Colorado Buffaloes got what could be its first and only win of the 2012 season in stunning fashion. But the most startling performance of the weekend has to go to Todd Graham and the Arizona State Sun Devils.

College football's Week 4 slate doesn't feature a ton of huge matchups, but there's plenty of impact games. Florida State-Clemson is a marquee ACC battle between two top-10 teams, while Michigan travels to Notre Dame. As usual, the SEC always has a few intriguing contests that are must-see games. Vanderbilt travels to Georgia, LSU hits the road for a matchup against Auburn and new SEC member Missouri takes on South Carolina. 

College football’s fourth week of action features a huge showdown in the ACC Coastal Division, a big matchup in South Bend between Michigan and surging Notre Dame and key battle in the Big 12 between Kansas State and Oklahoma.

The Pac-12 is a really good football league. And while Arizona State and Cal barely missed huge upset wins on the road in the SEC and Big Ten respectively, the league is still nipping at the heels of the SEC for national supremacy.

The Pac-12 continues to show its depth as the second-best league in the country. But it might have cost them a national championship contender. And Stanford was the culprit that both illustrates the strength of the league while also potentially knocking USC out of the BCS title game. The run the Cardinal are on against the Trojans is remarkable and will only make the North Division race that much more interesting. Meanwhile, the South Division just got extremely intriguing.

College football's Week 3 slate is full of interesting action. Arkansas had a surprising defeat to Louisiana-Monroe last week but has a chance to knock off No. 1 Alabama this Saturday. The Razorbacks are heavy underdogs and could be without starting quarterback Tyler Wilson. The action in the SEC isn't limited to Arkansas-Alabama, as Florida-Tennessee meet in Knoxville for a crucial East Division showdown.

After two weeks of action, it has become clear that the Pac-12 is much better than originally believed. Week 2 featured landmark victories over major powers from the Big Ten (Nebraska, Wisconsin, Illinois) and Big 12 (Oklahoma State) as well as victories over the ACC (Duke) and Big East (Syracuse). However, the same couldn't be said for Pac-12 contender wanna-be's Washington and Utah — both of whom now need to pick themselves off the mat after crushing defeats.