Colorado coach Tad Boyle has never been angrier after a loss during his tenure in Boulder than he was following the Buffs' flop against last-place Oregon State at home Saturday.

You might think he would have been more fired up having a win stolen from him at Arizona earlier this year. Nope. Losing to a last-place team on senior day with so much left to play for in terms of seeding in the postseason irked him quite a bit more.

Boyle took the blame when he apologized to the crowd immediately afterward, but the question that went unanswered in the aftermath is how a team with so much to play for could show up with "no sense of urgency whatsoever," as guard Askia Booker put it?

The loss will certainly affect the Buffs' position in the postseason and if they allow the Beavers to beat them again Wednesday in the first round of the conference tournament in Las Vegas, who knows how the NCAA Tournament selection committee might view them at the end of the week?

The Buffs (20-10, 10-8) will be the No. 5 seed in the rematch with the 12th-seeded Beavers (14-17, 4-14) at the MGM Grand Garden Arena (3:30 p.m., Pac-12 Network). It is the first year the conference has held its men's tournament in Las Vegas.

Colorado was forced to win four games in four days a year ago to capture the Pac-12 Conference's automatic berth to the NCAA Tournament. It could have avoided the same challenge this year by taking care of business Saturday. Instead, the Buffs are back in the same boat except that they are missing many of the playmakers and leaders most responsible for fueling last year's postseason run.

A year ago, Boyle's team had stellar leadership from seniors such as Carlon Brown, Nate Tomlinson and Austin Dufault. It also had a healthy Andre Roberson, who is the primary leader of this year's team, not to mention its best defender and the nation's leading rebounder.

Roberson is battling "a viral illness" that the Camera has been told is Mononucleosis and might not be able to play again this season, though Boyle has said he believes his star will return soon. The Buffs missed him badly Saturday and have to take a different approach against the Beavers to advance.

"We have to figure out a way to score against the zone, we have to figure out how to guard them better than we did in the second half, we've got to out-rebound them," Boyle said. "On paper, Oregon is a better offensive rebounding team than Oregon State. But Oregon State came in here and got 14 offensive rebounds, Oregon got nine.

"So it's not our opponent, it's us. One of the things we talk about a lot is if you as a basketball team don't take care of the problems you have on the court, your opponents will take care of those problems for you. That's what happened today. Our opponent took care of our problems -- not boxing out, not getting stops, they took care of it for us."

Oregon State has to enter the tournament with a much greater level of confidence than it otherwise would have coming off a win over its first-round opponent on its home floor. Several Oregon State players said they welcome the challenge of trying to beat CU a second time in five days.

OSU forward Eric Moreland had a double-double with 17 points and 10 rebounds Saturday.

"Regardless of who we play, we have to go hard because we're last in the Pac-12," Moreland said. "We have to go in and people can't sleep on us."

Joe Burton came up one rebound short of a double-double with 10 points and nine boards. Burton said he once faced the same team three games in a row.

"We've just got to come out with the same intensity and same game plan," Burton said.

Meanwhile, CU must completely change it up.

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