Miller, who averaged 3.2 points per game entering the night, was 6-of-7 shooting, made 6-of-8 free throws, grabbed five rebounds and had two steals.
"Tony is just different. He is quick and long and can score near the basket and get rebounds. Not afraid to stick his nose in there and take a charge," said Washington State coach Kyle Smith. "It is welcome especially because it is his first year in the program. He embodies what we preach. He has a great attitude and works hard. That motivates the other guys to play hard."
Four Washington State players scored in double figures and Jaylen Shead had eight rebounds, nine assists and three steals in addition to six points.
The bench of Washington State (4-4) stepped up, outscoring the Vandals 38-16 on a night when the Cougars leading scorer CJ Elleby was held to 10 points on 3-of-12 shooting. The Cougars were also more physical on both ends of the floor, winning the rebounding battle 39-29 and had 12 steals.
Despite forcing a season high 16 turnovers on Washington State, Idaho (3-6) was unable to hang with the Cougars in the second half. Scott Blakney had 13 points and Trevon Allen finished with 12 for the Vandals.
"A lot of credit for Washington State coming over here and competing and playing hard," said Idaho coach Zac Claus. "They did a good job of frustrating us offensively. I love how that kid Miller plays the game. I thought he was really productive, and they stayed with it as a team for what they were trying to accomplish."
Washington State: After going 1/3 at the Cayman Islands Classic, the Cougars get a much-needed win over regional rival Idaho.
Idaho: The Vandals have lost three in a row and are now 3-6 for the season, after going 5-27 a year ago when they only beat three D-I teams.
TURNOVERS: Entering tonight's game, the Cougar's turnover rate on offense was best in the nation at eight per game.
LONG RIVALRY: This was the 115th year in which the Vandals and Cougars played against each other. It is the longest rivalry west of the Mississippi.
Washington State: The Cougars travel to Spokane, Washington, on Saturday to play New Mexico State.
Idaho: The Vandals play Cal State Bakersfield at home on Dec. 14.
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