Blame the alarm clock.
Say that UCLA rolled out of bed too late for its morning game against Arizona.
Say the Bruins sleepwalked through the first 20 minutes, falling too far behind to recover when they finally woke up in the second half.
That would be the most convenient explanation for a Saturday that began with a 10 a.m. tipoff and ended with a sluggish 77-63 loss to Arizona at Pauley Pavilion.
"We've just got to be better prepared," guard Malcolm Lee said. "Even if we had to get up at 6 . . . because, as you see, they jumped out on us."
From his perspective on the bench, Coach Ben Howland witnessed a different scenario unfolding.
While Howland agreed that his players fell short of the required defensive intensity, he saw them playing too quickly at the other end of the floor.
"Everybody was rushed," he said. "We were forcing shots instead of being patient and letting those shots come to us."
Whatever the reason, the Bruins fell flat in a game that started early because of network television. They could not build upon a mini-run of three straight victories, their record slipping to 6-8, 1-1 in conference play.
The Wildcats improved to 7-7, 1-1, their coach offering yet another opinion, pointing to a decisive edge on the boards.
"We are all doing a lot better with rebounding," Sean Miller said. "It's not just one person, but definitely a team effort."
Coming off a cold shooting performance against USC on New Year's Eve, Arizona seemed intent on starting fast.
Guard Kyle Fogg penetrated at will on his way to a career- and game-high 25 points. Forward Jamelle Horne, who finished with 17, got open for three-pointers along the perimeter.
The Bruins could not keep pace. Not even close.
It was a dramatic change from Thursday, when they enjoyed their best start in a decade, shooting 83% against Arizona State's zone defense in the first half.
This time, facing an aggressive man-to-man, the team managed only 21%, with its top three scorers -- Lee, Michael Roll and Nikola Dragovic -- a combined one for 14.
"And those are the guys we want to shoot," Howland said.
With the score 35-20 at halftime, the defensive side of the story was equally disheartening.
The Bruins not only struggled against Fogg and Horne, they could not contain freshman Derrick Williams, who scored 16 points in the paint.
As the minutes ticked by, there was no reappearance of the zone that had worked so well against Arizona State. Howland explained that with Arizona grabbing 10 offensive rebounds in the first half, he could not afford to switch.
"The worry is that they're going to hurt you even worse on offensive rebounding," he said. "That's why you stay in man."
The second half went a little better, at least offensively, the Bruins shooting 60% with Lee and Roll scoring 15 points each after being blanked in the first half. But they could not quite manage the defensive stops to cut the gap.
"Fighting back the whole game is draining," Roll said. "A couple times we were right there, ready to climb over the hump and, aw, they would score or something would not go our way."
Lee had a particularly rough day, pressing his way to five turnovers. A previously undisclosed injury to point guard Jerime Anderson also might have hampered UCLA.
Late last week, the sophomore "re-tweaked" the groin injury that has pestered him in recent seasons, Howland said. He played 25 minutes, recording four points and four assists.
Add it to the least of possible reasons for UCLA's shoddy performance.
Now the Bruins can look forward to a trip north and a daunting matchup against California, a team picked to finish ahead of them in the conference race.
At least that game starts in the evening.