With all of the attention Cal forward Kristine Anigwe mandates, it’s easy to overlook the player often standing right next to her.

That won’t be the case much longer, considering the opening week of Pac-12 play.

Penina Davidson, probably the least celebrated of the Bears’ starting five, was all of a sudden their best player while splitting games at the Arizona schools last week.

She had her first career double-double (12 points, 14 rebounds) in a victory over Arizona and followed that with career highs in points (19), steals (three) and blocked shots (three) in a double-overtime loss to Arizona State.

“I just do whatever is needed that day,” the 6-foot-3 junior forward said. “If it’s going to help the team, that’s what I’m going to do.”

Davidson is able to fill a variety of roles for Cal, partly based on early playing experience. While traveling with New Zealand national teams, she would pick up different pieces from the styles being played in other countries.

She’s averaging 8.4 points on 50 percent shooting, 6.4 rebounds and 1.5 blocked shots per game.

All of that will have to be on display this weekend as the No. 20 Bears (13-1, 1-1) host the Oregon schools, starting with No. 16 Oregon State (13-1, 2-0) at 6 p.m. Friday.

The Beavers have won 10 straight and lead the conference in scoring defense (53.5 points per game). Oregon State has claimed at least a share of the Pac-12 regular-season title the past two seasons and reached the Final Four last year.

Being the underdog is nothing new to Cal, which was picked to finish sixth in the media’s preseason poll.

“We remember what it was like to lose,” Davidson said. “Even though we were on this winning streak, we were never complacent. We do not want to take a turn back.”

The Bears went 15-17 last season, with a 4-14 conference record.

“It’s difficult when you know what you’re capable of doing and you’re not necessarily performing that, but the Pac-12 tournament was basically a start to proving what we can do,” Davidson said. “I would argue that losing can actually bring a team closer together than winning, because you’re all in the slump together.

“Everybody counts you out, and you have to rely on each other, because you don’t have anyone else supporting you.”

Because they’ve gotten so close, Davidson considers her teammates part of her family. It’s a significant turn of events since she almost didn’t come to Berkeley.

Set on attending Stanford, Davidson didn’t have a backup plan. When she didn’t academically qualify for the Cardinal, Davidson’s name was brought to the attention of Cal head coach Lindsay Gottlieb by Stanford head coach Tara VanDerveer.

“I probably wouldn’t be here without her,” Davidson said of VanDerveer. “I hit culture shock, but not necessarily for the bad. Berkeley is so aware of what’s going on in the world, and it is starting to become home.”

Her brother, Isaac, is a freshman at Sonoma State, and if she misses the rest of the family, Davidson need look only at her arms. She has a tattoo on her right forearm that represents her mother, and her siblings’ names are inked on the inside of her left wrist.

“Much to my mother’s dismay,” Davidson joked.

Rusty Simmons is a San Francisco Chronicle staff writer. Email: rsimmons@sfchronicle.com Twitter: @Rusty_SFChron

Friday’s game

Who: No. 16 Oregon St. (13-1, 2-0 Pac-12) at No. 20 Cal (13-1, 1-1)

Where: Haas Pavilion

When: 6 p.m.

TV: Pac-12 Network