A reserve without reservation

BERKELEY -- Russell Westbrook, assist leader of the Pacific 10 Conference, UCLA’s premier perimeter defender, a lanky sophomore who seems able to bend and not break no matter how many hard knocks he takes, shrugged his shoulders and said “why not?” when Coach Ben Howland told him he wouldn’t start for a while.

“That’s the UCLA way,” junior forward Alfred Aboya said. “I think the coaches here do a good job of recruiting good players. But not only good players but good people with good character.”

The fifth-ranked Bruins (13-1, 1-0) will play California (10-2, 1-0) today at Haas Pavilion with a shortened bench and evolving roles. And several of them have proved gracious this week instead of cranky in accepting Howland decisions that seem best for the team if not always for the individual.

When junior swingman Michael Roll ruptured a tendon in his foot Monday in practice, it threw UCLA’s rotation for a loop.

Roll was the only perimeter substitute for Darren Collison, Josh Shipp and Westbrook. His loss for at least three weeks -- and probably longer -- sent Howland and his staff into the film room.

Howland pulled an all-nighter, a middle-aged coach studying as if he had a pass-fail midterm.

The decision he made was difficult. For now, Westbrook will come off the bench. Aboya, a gentle person and a ferocious basketball player, has become a starter.

Measuring his words carefully, Howland described Friday how difficult the decision was. “It bothered me for a while,” Howland said. “At the end of the day, it is what it is.”

Partly, it was a gut decision, Howland said. Partly, it is an experiment. Mostly, it is a necessity.

“The bottom line is, we had four perimeter players getting major minutes,” Howland said. Now it’s three and, Howland said, “they can’t all start or no one is coming off the bench for them. Russell’s one of our top five players and it makes it hard.”

Westbrook said he was “fine” with the decision. “Doesn’t matter,” he said, “as long as I play and we win.”

Westbrook isn’t the only one making a sacrifice.

There has been a domino effect. With Aboya as the starter at power forward, Luc Richard Mbah a Moute was moved to small forward.

Sophomore forward James Keefe had been planning to redshirt this season while he recovered from left shoulder surgery last August. He was called back to duty, playing his first game Thursday in the Bruins’ 76-67 victory at Stanford. He got only four minutes and his one shot, a three-pointer, rimmed in and out. “James will play much more,” Howland said. “I’m confident about that.”

Howland said he gave Westbrook the news in the locker room before Wednesday’s practice. “He didn’t blink,” Howland said. “He is the best. Russell is all about the team and I love Russell for his selflessness. He really is a leader.”

It isn’t only the players who need to find comfort levels. Howland likes to rely on repetition. He prefers to see Roll coming in after the first five minutes or Lorenzo Mata-Real stepping in after eight minutes.

“That’s how I’ve always been,” Howland said. “I like to get into a rotation of guys coming in and out after five minutes, after the first four minutes. Jordan Farmar knows when he’s going into the game for the Lakers, and when he’s coming out.”

If it gave Howland a knot in his stomach to keep Westbrook on the bench, it energized the coach to see Aboya embrace his starting spot.

Howland said he thought Aboya, with his imposing physical presence, could have been a dangerous football defensive end. He also noted that Aboya had sent Stanford forward Fred Washington into a shivering fall while going for a steal.

“Did you think that was a foul?” Aboya asked, not altogether innocently. “I got the ball first.”

Aboya is on track to graduate in June with a degree in international relations. Aboya said he was torn about whether to play his senior season for UCLA if he gets his degree, or go home to begin a career in government work.

“Right now, I can’t tell,” Aboya said. “It’s obviously a hard decision. You have to talk to people that are important to you -- your family, your coaches -- and decide what’s best for you and for them. As for now, what I have in mind is California tomorrow and the Pac-10 season.”

Roll left the team Friday morning. When his mother Joyce returned to the team hotel Thursday night, she was told her father had died. Howland said Roll returned home with his family.

TODAY

at California, 3 p.m., FSN Prime

Radio -- 570.

Site -- Haas Pavilion, Berkeley.

Records -- UCLA 13-1, 1-0 Pac-10; California 10-2, 1-0.

Update -- The Bruins have won three straight games at Haas but lost their last meeting with the Bears, 76-69, in a quarterfinal of the Pac-10 tournament last March. While sophomore forward Ryan Anderson leads the Pac-10 in scoring (21.6), California has become a hot-shooting perimeter team lately, making 37 of 76 (48.7%) from three-point range in the last three games, including 11 of 25 in Thursday’s 92-82 win over USC. Sophomore point guard Jerome Randle, a transfer from Duke, is averaging 13.7 points and has 40 assists in 10 games. He was Pac-10 player of the week last week after averaging 23 points and shooting 59.1% in two games in the Golden Bear Classic.

diane.pucin@latimes.com