​Mater Dei players celebrate after beating Sierra Canyon in four sets to win the CIF Southern Section Division 1 championship on Saturday. (Steve Galluzzo / For The Times)Upon hammering her 19th kill on a cross-court attack, Westley Matavao leaped into the arms of her teammates to celebrate Mater Dei’s 24-26, 25-23, 25-21, 25-23 triumph over Sierra Canyon in the CIF Southern Section Division 1 girls’ volleyball final Saturday night at Cerritos College.Having avenged a loss in the section finals last season, the Monarchs’ next goal is to defend their state championship, and they will be the top seed when the Southern California Regional Open Division bracket is released Sunday.Westley Matavao goes on the attack for Mater Dei against Sierra Canyon in the CIF Southern Section Division 1 girls’ volleyball championship match on Nov. 7, 2026. (Steve Galluzzo / For The Times)“This season it’s important for us to win everything because I’ve been here all four years, this is my last one and I wasn’t going to take losing as an answer,” said Matavao, a senior outside hitter headed to UCLA.The Monarchs (39-1) have dealt Sierra Canyon (32-2) its only losses this season and the top two programs in the nation could meet for a third time, but for now Mater Dei reigns supreme after earning its second section title in three years. It swept the Trailblazers in the finals two years ago.Freshman Jimin Seung had 14 kills, Cal-bound middle blocker Emma Kingston had 11 kills and sophomore libero Sienna Cicero finished with a match-high 23 digs, diving all over the floor to keep points alive.“It was definitely tougher this time around — over half of them are high Division I level players — so you can’t underestimate a team like that,” Cicero said. “Our blockers played great and funneled the ball perfectly for me. My mentality is we’re going to win no matter what.”Mater Dei beat Sierra Canyon, 25-18, 25-17, in the gold division final at the Durango Fall Classic in September before suffering its only loss to Trinity League rival Santa Margarita 11 days later.Katherine Nowak, center, celebrates a kill with Mater Dei teammates Jael Smith, left, and Riley Stringer against Sierra Canyon in the CIF Southern Section Division 1 final on Saturday. (Steve Galluzzo / For The Times)Sierra Canyon trailed by seven points midway through the first set but rallied to take an 18-17 lead on an ace by McKenna McIntosh, who blasted through a left-side block on the Trailblazers’ first set point. McIntosh, a hitter headed to USC, finished with 10 kills and 19 digs and Nebraska-bound middle blocker Kendall Omoruyi had a match-high 22 kills.The Monarchs were clinging to a 21-20 lead in the second set when Matavao took control, hammering spikes for her team’s last four points. An ace by Kalea Lee gave Mater Dei a 21-19 lead in the third set and another by Matavao had the Trinity League champions one set away from victory.Lee (22 assists) and fellow setter Rile