PULLMAN, Wash. (AP) Oregon State Beavers won ugly, beating Washington State Cougars 85-77 on Saturday afternoon to clinch a first-round bye in the upcoming Pac-12 Tournament.

Tres Tinkle scored 26 points and grabbed 12 rebounds as the Beavers came up big on defense late in the second half to spoil the Cougars' senior night.

''It wasn't a thing of beauty but our guys stepped up when we needed them to and we showed great toughness,'' Oregon State coach Wayne Tinkle said. ''They kept fighting and I couldn't be more proud of this group.''

Stephen Thompson Jr. added 26 points for the Beavers (18-12, 10-8). Ethan Thompson scored 17 points with 11 assists and five rebounds and Kylor Kelley added 10 points.

Oregon State is 11-0 this season and 6-0 in conference play when four or five players score in double figures.

Robert Franks scored a career-high 37 points and grabbed nine rebounds for Washington State (11-20, 4-14), which has lost five straight. Jeff Pollard added 13 points and CJ Elleby grabbed 12 rebounds.

''(Franks) is just one of those special players and he wasn't that way when he came into the program but to his credit he developed himself into that,'' WSU coach Ernie Kent said.

Oregon State took its first lead, 46-45, in the opening minutes of the second half after an 8-0 run capped by Kelley's 3-point play.

Thompson Jr.'s jumper and 3-pointer capped a 7-0 run for Oregon State over 2:24 and the Beavers blew the game open with a 10-0 run over 2:14. Back-to-back 3's from Zach Reichle and Thompson Jr. sparked the run and Alfred Hollins' jumper gave OSU a 16-point lead with five minutes remaining.

WSU closed to within six points with 27 seconds left on Franks' 3 and two free throws, but the Cougars got no closer.

The Cougars raced to a 9-2 lead, with Franks scoring six of the first nine, and shot 83 percent from field goal range and 3-of-4 from behind the arc in the game's first five minutes.

''We came out a little too soft, there wasn't the urgency we needed to get to Franks he got on a roll from the first couple possessions,'' coach Tinkle said. ''We needed guys to step up and I am really proud of Tres for getting some things going offensively to keep us in it and keep us believing at halftime.''

Oregon State weathered another WSU run midway through the first half after Franks ignited the crowd by hitting a deep 3-pointer while being fouled. Franks made the free throw for a 4-point play, putting the Cougars up 23-11.

The Beavers answered, with Tinkle hitting back-to-back 3's within 48 seconds of each other, but the Cougars led 43-38 at halftime behind Franks' 20 points.

BIG PICTURE

Oregon State: The Beavers are 1-1 in their final road trip of the regular season before heading to the Pac-12 Tournament. Oregon State needs to win the Pac-12 Tournament to earn an automatic bid to the NCAA Tournament.

Washington State: The Cougars have lost five games in a row for the third time this season in the run-up to the Pac-12 Tournament.

UP NEXT

Oregon State: travels to Las Vegas to play in the Pac-12 Tournament.

Washington State: travels to Las Vegas to play in the Pac-12 Tournament.

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