The second half of the Pac-10 season starts at Maples Pavilion tonight, with a 7 p.m. tipoff between the Cardinal and the Bruins.

Undefeated at home all season, No. 2 Stanford

(19-1, 9-0 Pac-10) will play host to its closest challengers this week, as UCLA (14-6, 7-2) and USC (13-7, 7-2), the Cardinal’s opponent on Sunday, are tied for second in the conference.

Apart from unanimous No. 1 UConn, UCLA is the team that has played Stanford closest all year, losing out in Los Angeles by just four points. Even with home advantage on the side of the nation’s second best team, it should be a challenging game.

UCLA swept the Oregon schools at home last week, beating the Cardinal’s 100-80 win over Oregon with a 104-80 mark, and freshman forward Markel Walker claimed the Pac-10’s current Player of the Week award, having posted back-to-back double-doubles in those contests.

The Bruins will be hoping to repeat the form they showed in the second half of the game in L.A., coming back from a 16-point deficit to challenge Stanford right until the final seconds.

“If we don’t come out and if we’re not playing aggressively, they’re a very explosive team so they can kind of get hot,” said Stanford head coach Tara VanDerveer, “and [in L.A.] we didn’t go over some screens and they hit some shots on us.”

“They’re a very aggressive team — they’re a team that presses and traps, and they’re a very good shooting team,” she continued. “So they’re not big inside, but they’re very aggressive and they’re very physical.”

This style of play, especially on defense, should differ from the style exhibited by Arizona last Saturday, where Stanford’s two starting guards were able to score just one three-pointer between them. In contrast, redshirt senior guard Rosalyn Gold-Onwude collected a then-career record haul of 18 points (since bettered with 19 against Arizona State) in the first matchup between the Cardinal and the Bruins.

“I definitely think that certain games suit certain players better,” Gold-Onwude said. “I think a game like UCLA brings out the best, because they’re all up on you, they’re pressuring, so you have the opportunity to come hard off of screens, curl, drive and then also knock down a three if you’re wide open.”

Having secured its 40th consecutive home victory against Arizona, the Cardinal enters Thursday’s matchup on a six-game streak against the Bruins. And with a commanding 44-22 all-time record, the team knows what it needs to do to win.

“We have to play our game, which is getting touches and looks for Nneka [Ogwumike] and Jayne [Appel] and Kayla [Pedersen] and Joslyn [Tinkle],” VanDerveer said. “And then our perimeter people working really hard defensively, getting some steals, getting out and running better. And we have to do a great job on the boards . . . and then just really knocking down shots.

“But beyond that, it’s letting the offense come to you, not pressing, not forcing things, being patient and letting the offense come to you,” she said.

However, this game — and the final eight that follow it in the conference — comes at a difficult time for the team.

Key players have either been kept out of action or had their minutes restricted in important games recently, and, as if to rub salt into the wound, it seems the problems are contagious. Gold-Onwude injured herself in practice this week, while junior forward Kayla Pedersen tweaked her ankle. Senior forward Jayne Appel, nominated yesterday as a finalist for the Lowe’s Senior CLASS Award, has been unable to train due to a swollen foot, and sophomore guard Grace Mashore has also been sidelined.

Whether or not other players can step up to fill in for their injured teammates will be a crucial test for the team if it hopes to take both the Pac-10 and NCAA crowns at the end of the year.

However, though the biggest obstacle to achieving that dream of a national title will be UConn — the only team that has beaten the Cardinal in the last 12 months — the season is more than just a single game.

“We definitely always remember that we’ve lost to UConn,” Pedersen said. “That gives us a lot of motivation. But we don’t really look at it like we’re undefeated in the Pac-10 — we just keep each game, like, game by game. USC just lost to Oregon, so things like that can happen, and we don’t want any team to sneak up on us like that.”

It has been a great first half of the season for Stanford, but nothing is yet decided. The Cardinal tips off against UCLA tonight at 7 p.m. at Maples Pavilion.