LAS VEGAS — Ehab Amin scored 17 points, Miles Norris added 14 and Oregon rolled over Washington State 84-51 Wednesday night in the most lopsided game in Pac-12 tournament history.

The sixth-seeded Ducks (20-12) jumped on the Cougars from the start, racing out to a 15-point lead in the opening 12 minutes. Oregon shot 49 percent from the floor and had 14 steals to earn a spot in Thursday’s quarterfinals against No. 3 seed Utah.

The tournament’s largest margin of victory had been 32, accomplished twice.

Washington State (11-21) shot 31 percent, went 7 for 32 from the three-point line and didn’t hit double-digits in points until the 5:34 mark of the first half.

The 11th-seeded Cougars also had 20 turnovers that led to 26 Oregon points in their ninth straight one-and-done trip to the Pac-12 tournament.

Washington State had no players score in double figures.

The Ducks closed the regular season with four straight wins, including their second double-digit win over the Cougars.

USC drops Arizona

Bennie Boatwright had 22 points and 11 rebounds, helping USC roll over Arizona 78-65 in the opening round of the Pac-12 tournament.

The eighth-seeded Trojans (16-16) started slowly, but went on 18-2 runs in each half to earn a spot in Thursday’s quarterfinals against top-seeded Washington.

Derryck Thornton scored 12 points and USC shot 48 percent to bounce the ninth-seeded Wildcats from the Pac-12 tournament after losing to them in the title game a year ago.

Arizona’s difficult season might have come to an end with its first opening-round Pac-12 exit since 2010.

The two-time defending champion Wildcats (17-15) continued to be embroiled in a recruiting scandal and struggled on the court, punctuated by their lopsided loss to the Trojans.

Unless Arizona gets an invite to a smaller tournament, it will not play a postseason game for the first time since 1983-84, Lute Olson’s first year as coach.

The school also must decide the fate of coach Sean Miller. He has repeatedly been linked to the recruiting scandal and will be subpoenaed in a federal trial next month.

Miller stuck to his stance of not commenting on questions concerning the scandal or his job, saying “No” when asked if he thought this was his last game at Arizona.

UCLA downs Stanford

Jaylen Hands had 22 points and 11 rebounds, helping UCLA hold off Stanford 79-72 in the opening round of the Pac-12 tournament.

The seventh-seeded Bruins (17-15) built a 26-point lead before Stanford started hitting shots in the closing minutes to pull within 69-62.

UCLA hit 10 of 12 free throws in the final 1:05 to earn a spot in Thursday’s quarterfinals against No. 2 seed Arizona State.

The 10th-seeded Cardinal (15-16) struggled against UCLA’s defensive pressure early, finishing at 35 percent from the floor and 7 of 25 from behind the three-point arc.

Josh Sharma had 18 points and 13 rebounds, and Marcus Sheffield added 18 points to lead Stanford.

Colorado beats California

McKinley Wright IV scored 18 points and Colorado held off California 56-51 in the opening round of the Pac-12 tournament.

The fifth-seeded Buffaloes (20-11) had a hard time holding on to the ball, committing a season-high 23 turnovers, but made up for it by shutting down the Bears defensively.

Colorado used an eight-point burst midway through the second half to go up 10 and held off a late Cal charge to remain undefeated (8-0) in Pac-12 tournament first-round games.

The Buffaloes move on to face No. 4 seed Oregon State in the quarterfinals.

The 12th-seeded Bears (8-23) shot nearly 50 percent while winning their final three regular-season games, but reverted to their shooting struggles in the Pac-12 tournament.