Colorado's head coach challenged his team to ratchet up the intensity on the defensive end.
The Buffs held Washington to 33.9 percent shooting from the field and out-rebounded the aggressive and athletic Huskies 38-37 on their home floor.
So despite CU's 64-54 loss, which dropped the Buffs to 11-6 overall and 1-4 in the Pac-12, Boyle was encouraged after Wednesday night's game here at the Alaska Airlines Arena.
"I thought our defense was good enough to win," Boyle said. "Our guys' effort was great. We played with pride, we played with some toughness, and we lost to a good basketball team."
CU trailed 39-34 midway through the second half after Josh Scott scored down low on two consecutive possessions.
Then the hustling Huskies grabbed seven offensive rebounds over a span of 2 minutes and 27 seconds, which allowed the home team to surge ahead 48-38.
"The offensive rebounding really killed us in the second half," Boyle lamented. "We had some stops and we couldn't finish the possession with getting the rebound."
Despite the regrettable sequence, the Buffs finished the game with an 11-9 edge in second-chance points and outscored Washington 32-18 in the paint.
CU's players said they will pack confidence with them on the trip to Pullman for Saturday's game at Washington State.
"I definitely think we stepped up big time on the defensive end. We just didn't get the rebounds when it mattered," Andre Roberson said after grabbing 11 boards and scoring 10 points. "We didn't get the tough ones and the stops. They had too many possessions when they had multiple shots at the basket."
Washington, now 12-5 overall and 4-0 in the conference, played with even more grit than the visitors.
The Buffs made only 7 of 24 shots in the first half and finished the game shooting 36.2 percent from the field. Aziz N'Diaye, a 7-foot senior, had three of the Huskies' five blocks and and finished with 11 rebounds (five offensive). Desmond Simmons added 12 boards (three offensive).
CU was 1-for-10 from behind the arc and awarded only 14 free throws. Washington made six 3-pointers and 18 free throws.
"We always knew we could play good defense," Washington guard C.J. Wilcox said after scoring 25 points on 8-for-14 shooting on an otherwise ugly night of offense. "We came into the season saying that's what we need to do. It took some time to finally get it through our heads that this is the way we need to play."
CU allowed Arizona (43.1), Arizona State (42.6), USC (41.4) and UCLA (51.7) to all shoot above 40 percent from the field during a disappointing 1-3 start.
Wednesday's defensive performance leads Boyle to believe the Buffs are on the verge of getting back on the right side of the "thin line" between winning and losing in the Pac-12.
"I think we showed signs of improvement, big strides on the defensive end," Spencer Dinwiddie said after leading CU with 15 points. "If we continue this pride on defense, things will turn around real quick. ...
"We've got a ton of talent and we don't think we'll shoot like that again because it was very terrible. If we build on what we can do, which we showed we can play defense, we'll be fine."
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