The way I saw it, this game clearly had four distinct parts to it.
Part One lasted for about the first seven minutes of the first half. Both teams were running a 2-3 zone defense and not many shots were going down on either end. The Cougars had a little more shots fall, so they eventually had an early lead.
Part Two is where the Cougars shots really started to fall. By analyzing the game flow graph. You can see that this is where the Cougars pulled away in the first half. Everything was running well on offense. They were getting good penetration off the dribble and moving the ball nicely. It looked like this game might be a blowout. But...
Part Three is when Oregon State began running their half court trap. It happened at about a score of 34-20 or 41-22... I can't remember. But the key was that Oregon started doing it when they fell way behind by double digits. This trap almost spelled doom for the Cougars...
The Beaver trap started with two guards running to trap the ball carrier the moment he passed half court. A third player would loosely guard both our second wing player and the far side baseline player. This player was ready to take an errant pass or pounce on the next ball handler. There would also be one big positioned around the top of the key or the elbows. This prevented any lob passes to Casto or whoever might be positioned under the basket. A third smaller player was left to guard the player on the near side baseline and also to help guard Casto or whoever of our bigs might be prowling around under the hoop. I'm not very experienced with Xs and Os, so perhaps someone else who was at the game might be able to explain it better. I made my own paint image from what I remember about the trap but I'm not sure how or if it's possible for me to post the image??? I can't tell you exactly with certainty how the defense would shift after the pass was thrown (usually to the other wing guard Klay <--> Reggie) but it always resulted with two defenders crashing on the guy with the ball. I didn't play basketball in high school, so this trap may be second nature to someone out there and they will recognize what I'm talking about instantly. I'm linking a google image that I think best represents this trap.
So from the start the Cougars came at this trap by placing Thompson on one wing and Moore on the other wing and simply having them toss lob passes back and forth until something became open. Two other players were placed at the baseline corners and the 5 was placed well... in the center of course. Obviously it looked like Bone was trying to spread the court out. There wasn't very much off ball movement. No screens or anything. Just players trying to get open and pass the ball before they got trapped.
Well this didn't do much to break the trap. Reggie especially had the most trouble getting passes through the trap. Sometimes they were able to get enough lob passes in to inch their way towards the three point line and sometimes they created an open three opportunity. But beyond that, there was no offense and now the threes just weren't falling.
This part three of the game continued for the last part of the first half and into the second half. The Cougars were fortunate that nothing was working on offense for the Beavers at the end of the first half either, or else this game could have been much closer at half time.
Once the second half started the Beavers started to put more points on the board. This was in part due to some calls which sent them to the line as PitterPatWSU mentioned, but that wasn't the main reason.
The refs were not that horrible. It certainly was not one of the worst officiating performances I have ever seen. Not even close. Refs will nail us for nit-picky fouls that we won't agree with. That's what they do. It happens. There were some questionable calls in this game and one might venture to say that the most questionable calls were on us. But realistically this is probably not the case. It seemed a couple times that our guys were doing a good job of only giving minimal contact on defense but getting called anyway, but that is probably just me the passionate Cougar fan watching. Bobby McRoy (the black ref with the huge scar across his face) always seems to be our nemesis, but that wasn't the case in this game.
To begin the second half the refs called three straight fouls on us and OSU was able to get some unanswered free throws. But the officiating wasn't the reason why the Beavers started to creep back into the game. The big reason was some forced turnovers which resulted directly in baskets on the other end for OSU.
Part three persisted for a while and WSU struggled with the half-court trap. Ken Bone didn't have an answer immediately out of half time and OSU clawed their way back into the game; only down by four at one point.
However, the Cougars finally found away to break the trap and they did it in two ways:
The first was what Nuss mentioned in his post:
Ken Bone did what good coaches do and tweaked the offense for the situation, moving Thompson to the high post.
The second thing they did was up the tempo and push every fast break that they could. Klay Thompson came to realize that he could drive on these guys before they were prepared to set up the trap and he did that in what was probably the play of the game. Hopefully we'll all be able to see highlight reals of this. Klay split two defenders at half court and dribble the ball directly to the basket up and over another defender for the slam. This play absolutely ignited the crowd--which was rather quiet by the way with quite a few more parents in the student section than usual. But that is to be expected with WSU still being on break. I was actually quite impressed with the size of the crowd tonight.
So the Cougars amped up the tempo and there were a number of easy dunk shots that resulted from these two offensive changes. Casto, Capers, Thompson all participated in the dunk fest. Part Four of the game was in effect and the Cougars road this on to victory.