I'll discuss Oregon, UCLA, Cal and Stanford below:
With Oregon, they're going to be entering league play at 12-1. Overall their OOC is far easier than CU's, but they have played two very quality teams. Their one loss is to a Cincinnati squad that is on the verge of cracking the top 10. They also have a very solid win on the road against a top 25 UNLV team. They're going to need to really take care of business in conference play, but all indications are that they're going to do that. The Ducks under Altman are exceptionally successful on the road, and that's obviously a huge thing to have going for you in conference play.
It's easy to scoff at UCLA at this point, but they have a few things going for them. They've played some solid OOC teams, and still have #12 Mizzou and a halfway decent Long Beach State squad remaining. Yeah, they've lost to the good teams they've played (Georgetown and San Diego State) but we all know how RPI loves when you play strong teams, even if you lose. And, also, they're UCLA. Names matter. If, hypothetically, UCLA is on the bubble and a remaining spot is between the Bruins, and say, Miami (FL), with both teams having near identical resumes...i'll solve the mystery for you: UCLA will be selected. Lastly, UCLA is simply too talented, even taking their issues into account, not to rack up a solid record in conference play over 18 games in another suspect year for the Pac-12, IMO.
Cal's next two games are absolutely massive. Like, make or break the season games. They face UNLV and Creighton, both in Berkeley. With the Pac-12 being suspect, Cal obviously needs to win at least one of those to be remotely in the picture, but I think they may have to win both if they want to be considered legitimate contenders for the NCAA Tournament. I know it sounds harsh to say they need to win both, but Cal's best win right now is against a Georgia Tech team that is 10th best in the ACC. Aside from that, it is entirely cupcakes. Of course it's all extremely speculative this time of the year, but Oregon under Altman has a knack for winning road games that Cal isn't capable of. This is a golden chance for Cal: two top 25 teams on your home court. Beat them, and all of a sudden you're in decent shape heading into conference play.
Stanford already has their backs against the wall for any hope of making the Dance. They've faced two excellent teams in Mizzou and Minnesota, but lost both. They also have a home loss to Belmont that won't do them any favors (Belmont isn't bad, but it's not the type of game you can lose at home). They still face NC State and Northwestern in OOC play so the chance for quality OOC wins is there, but the problem is both of those are on the road. So, basically, Stanford is in extreme danger of heading into league play without a real quality win (they do have a halfway decent win over Northern Iowa, but UNI is likely middle of the pack MVC). That's a doomsday situation in a weak Pac-12.
I think it's quite possible we have a conference tournament with as many as 3 teams on the "bubble" in some way, shape or form. Assuming Arizona hangs around the top 10-15, they are going to be facing some desperate teams starved for a big win knowing that defeating Arizona is their only chance to really turn some heads.