PROVO — Kayla Walker was in the zone. The BYU senior right-side hitter scored career highs in hitting and hitting percentage. And to top it, all of the Cougars won their MWC opener against the San Diego State Aztecs in the Smith Field House in a five-game nail-biter — 25-19, 21-25, 24-26, 25-22 and 15-7.

After walking away with the opening game in methodical fashion behind Walker's first seven kills of the match, the Cougars fell apart, finding themselves on the losing end of the next two games.

"I think we let down. We out-hit them all night, but serve and serve receive is where it really matters," said BYU coach Shay Goulding, who noted that her team served up three errors and no aces in the second game and didn't improve much at that aspect until late in the fourth game.

"We need to continually be aggressive, but we started playing tentative. I think we're a great team, and we have to be able to hold onto our mental toughness," added Goulding.

Her team was playing a similar game in the fourth as they did in losing Games 2 and 3, and then suddenly, things turned completely around.

The Cougars were down 13-18 heading into the stretch run of Game 4 when they took a timeout and decided they didn't want to fall in their conference opener against the Aztecs and start the season with an 0-1 record in conference play.

"We just made a conscious decision during one of our time-outs that we were going to win that game," said Walker.

At that time, the BYU players went on a 12-4 run to finish the game, getting six straight points to go from 18-21 down to a 24-21 commanding lead. Fittingly, Walker finished the Game with her 29th kill of the night, giving her seven in each of the first three games and eight in the fourth.

But Walker wasn't finished. She added four more kills in the fifth game to give herself a career-high 32 kills for the match. Her .500 hitting percentage with only three errors in 58 attempts topped off a career night. And Walker's defense matched her offense as she punched up 12 digs in the process.

"There are definitely nights when you feel like you're in the zone, and this was definitely one of those nights. It was so much fun, even though we struggled a little in Games 2 and 3," Walker added.

Though the Aztecs had the Cougars on the ropes through much of the fourth game, BYU took charge in Game 5 and put them away easily, adding to their confidence in going forward in the season.

"Winning that game and getting the first conference match under our belts will be a big confidence boost for the rest of the season," said Walker, whose team fell to a pair of top 10 teams in Nebraska last week in four games each.

"Kayla had a fantastic night, but our goal is to spread the offense. But when we need to rely on her, she's there, and she shows up like that all the time in practice," said Goulding of her star.

Walker wasn't the only Cougar with big numbers, though hers certainly were through the roof. Christina Measom added eight kills and eight block assists to the effort, and Casey Speredon-Thurston finished with 13 kills. Nicole Warner also added eight kills for the Cougars.

The Aztecs were led by Kyley Sexton with 15 kills and Lauren Salisbury with 13 kills.

e-mail: jolsen@desnews.com