Posted by ESPN.com's Ted Miller

What did we learn from Week 4 of Pac-10 action?

1. Oregon might get the last laugh: How good a weekend did Oregon fans have? The Ducks rolled sixth-ranked California 42-3. Oregon State lost. Washington lost. Both sets of rival fans had been taking shots at the Ducks ever since they went rear-end-over-tea-kettle at Boise State. Even after a pair of quality victories, the latter one ending No. 18 Utah's 16-game winning streak, some were grumbling about new coach Chip Kelly and quarterback Jeremiah Masoli. Guess here is there will be no grumbling this week, at least on the Ducks side of things. Of course, Pac-10 frontrunners haven't been terribly secure of late.

2. It's gut check time for Cal: You look at California's roster. You look at the final score in Eugene. It doesn't make sense. The Bears have too many good players to get whipped like that. So how will the Bears react? We knew USC-Cal was a big game even in August, but the Bears season is now on the brink. Yet the timing probably couldn't be better for USC to visit Strawberry Canyon, where Cal is often a much different team than on the road. No way the Bears lose focus and feel sorry for themselves this week. They have an opportunity to get nearly all their mojo back against a vulnerable Trojans squad.

3. Arizona and Washington State found their QBs of the future: Nick Foles led a winning effort at Oregon State for an Arizona team that overcame huge injury issues. (And that Iowa loss looks a bit better today, eh?) Jeff Tuel led a losing effort at USC for a Washington State team that is playing much better football compared to 2008. Both give their programs hope. Foles for this season, where Arizona again looks like a bowl team. Tuel for the future, when the Cougars restock their talent.

4. Stanford is on the cusp of breaking through: The Cardinal bullied Washington with 321 yards rushing, and the defense played much better, holding the Huskies to 290 total yards and just one offensive TD. Think there's some regret about how the second half went at Wake Forest? Nonetheless, Stanford sits atop the Pac-10 with a 2-0 record in conference play. Another win or perhaps two and the Cardinal enters the Top 25.

5. The Pac-10 race is wide open: There will be no weeks off in the Pac-10 this year. Even Washington State has shown enough to toss off the patsy label. Oregon might be the latest flavor of the week, but is anyone really counting out USC? Or Cal? And what about Arizona State's effort at Georgia? The Sun Devils proved their first two games weren't a mirage. Of course, a competitive conference means a black-and-blue conference, and the nine-game round robin schedule means the likelihood of a team emerging unscathed is nearly zero. In fact, it's a good bet now that the eventual champion will win a tie-breaker among two-loss teams.