SEATTLE — A career performance by sophomore Cynthia Barboza nearly carried Stanford women’s volleyball to victory this weekend, but the offensive juggernaut of No. 4 Washington proved too much for the No. 6 Cardinal.

Splitting its opening weekend of conference play in Washington, Stanford (10-2, 1-1 Pac-10) swept past unranked Washington State (12-4, 0-2), 30-17, 30-16, 30-23, in the Pac-10 opener Thursday, but lost a tight three-game match, 30-21, 30-28, 30-25, to the defending national champion Huskies. Sophomore outside hitter Barboza’s 25 kills and two aces were match highs, but a smothering block and flawless hitting by two Huskies gave Washington (12-1, 2-0) the boost it needed.

“As a team, they played very well, executed well,” Cardinal head coach John Dunning said of the Huskies. “They taxed us and they showed us that, while I wouldn’t call them weaknesses, we definitely have some things that we need to keep working on.”

The Cardinal got the weekend off to a good start with a sweep of Washington State. The Cougars were no match for Stanford who took the first game 30-17. Though the teams were neck-and-neck early, with the score tied at 10, Stanford finally broke away with a 14-2 run. The Cardinal’s sixth block of the game, a double by Barboza and sophomore middle blocker Foluke Akinradewo, ended the frame with a bang.

Stanford hit .375 as a team and held the Cougars to a negative percentage in the first game. Senior outside hitter Kristin Richards hit five-for-seven in the game and Akinradewo blocked five balls, including two solo.

The Cardinal started more quickly in the second game, going up 4-1 and never looking back. Senior middle blocker Michelle Mellard served five straight points, including a pair of aces to stretch the lead to 15 at 27-12. Junior setter Bryn Kehoe’s fourth kill of the night ended the game 30-17.

Richards notched five more kills in the second, and the Cardinal recorded 18 kills with only two errors, hitting a spectacular .615.

After taking the 20-11 lead in the third game, Stanford gave up five points to the Cougars before rallying for the 30-23 victory. Richards closed out the night with two kills, finishing with a match-high 13 on .348 hitting. Barboza had 12 kills, while Akinradewo had seven to go along with seven blocks.

“Bryn set lots of good balls on Thursday,” Dunning said. “Her connection to the middles was great. It was key to control the ball and get it to the middle and Foluke and [junior middle blocker] Franci [Girard] were unstoppable.”

The next night, however, the Cardinal found themselves on the other side of a sweep, falling in three to the defending NCAA champs. Washington jumped out to an early lead and powered past Stanford for the 30-21 win in the first game behind the .833 hitting of Alesha Deesing (5-for-6).

The second game was even throughout, with neither team ever leading by more than three. The score was tied at 28-28, but the Huskies scored the two points they needed for the win.

As in the second game, the Cardinal kept pace with the Huskies for most of the game before falling back late. After the lead went back and forth, Washington claimed the win, 30-25, on a missed attack by Stanford.

“We came very close in that second game,” Dunning said. “If one play goes one way or the other, it can change the course of the game. But when they pulled away a bit in the third, it was hard for us to fight back.”

Barboza finished the match with 25 kills in the three games, one short of her career high. Sophomore libero Jessica Fishburn recorded a career-high 25 digs, with 10 coming in the third game alone.

“For Jess to have 25 digs in just three games, that was definitely the best defensive performance she has had,” Dunning said. “And Cynthia was hitting great and playing really well all around.”

Richards struggled with the Washington block, but nonetheless finished with 15 kills, putting her one ahead of Olympic gold-medalist Kerri Walsh on the career kills list with the seventh-highest total in school history.

After the disappointing result, the Cardinal are looking ahead to the rest of the season and their second shot at the Huskies, at Maples in late November.

“We have had some team conversations and talked to some individuals about things to work on,” Dunning said. “The team understands that the most important thing is to stay healthy and keep improving. And that has been our trademark in the past, to keep improving right up to the end.”