STOCKTON — Allie Walljasper had plenty to do with Sierra punching its ticket to the semifinal of the Sac-Joaquin Section Division IV softball tournament Wednesday night.

The Sierra junior hurler tossed 11 strikeouts and slapped a two-run homer against Ceres, which helped lift the reigning Valley Oak League champion and tournament’s No. 1 seed to a 7-2 quarterfinal victory at the Arnaiz Softball Complex.

The T’Wolves opened the playoffs with a 6-3 victory over Los Banos in the early game.

“I just wanted to see the ball and drive it,” said Walljasper, who went 2 for 3 with three RBIs and a run in the nightcap. “At first I didn’t think it was going out, but then I had enough power.”

Walljasper’s two-run jack to left center stretched the Sierra (12-2 VOL, 23-2 overall) lead back out to four after Ceres (19-11) had just cut its deficit in half during the top of the fifth.

After a scoreless second frame and Sierra already up 1-0 thanks to Walljasper’s first hit of the game — an RBI-single that scored Iyana Hughes — the T’Wolves created more havoc in the bottom of three. Sierra senior Sommer Wilson (2 for 3) tallied an RBI-double that scored Hughes for a second run, which was followed by a Lexus Barnes two-RBI single that scored Devi Coglio and Wilson to make it a 4-0 contest.

After a scoreless fourth, a youthful-laden Ceres squad finally got something going in the fifth frame. The Bulldogs got their first hit of the game off Walljasper when freshman Nicole Bates tripled to the warning track. Bates crossed the plate on a passed ball to make it 4-1.

“I’m proud of the way our girls played,” Ceres head coach Donnie Donaldson said. “We were facing, if not the best team, but the best pitcher in the district. We tried to limit strikeouts and we knew (Walljasper) had a good rise ball. But overall we’re a young team. We start six freshmen and a sophomore. We did compete until Allie hit that home run. It took the wind out of our sail.”

Ceres’ next six batters were retired in consecutive order, and four of those six were strikeouts. Walljasper gave up four hits with a walk. She also retired the side in three of Ceres’ seven at-bats.

Sierra added its final run in the bottom of the sixth when Katelynn Perkins connected with an RBI-double that scored junior varsity call-up Taylor Moss.

“We have two down, and it’s not going to get any easier from here,” Sierra head coach Nick Olmo said. “It starts pairing down and we’ll be facing the better of the crop right now. We’re hitting the ball and we’re seeing it, and we’re making the plays we have to make.

“Allie tends the throw harder as the games go on. The more innings she has under her belt, the harder she throws, and that was evident.”

Ceres’ second run came across when freshman MacKenzie Veuve hit a RBI-single that scored fellow freshman Sabrina Baisdon.

Like it did against Ceres, Sierra jumped out to a four-run cushion in its opening-round contest against Los Banos (8-4 Western Athletic Conference, 15-15 overall).

Sierra’s Walljasper pitched five innings and Wilson closed out the final two. Hughes scored the T’Wolves’ first run of the contest via her alert base running. Walljasper recorded an RBI-double to make it 2-0 and Barnes hit an RBI-single that scored Katelyn Teixeira to make it a three-run contest. Julie Deanda also had an RBI-single that made it 4-0.

Los Banos senior shortstop Alexis Barcellos hit a two-RBI double that plated two runs and made it 4-2.

Sierra’s lead-off hitter and senior Hughes tallied an RBI-triple that scored junior Gianna Lenoci to stretch the Sierra lead back out to three. Hughes also scored in that inning to get Sierra’s two runs back.

“We know we still have two tough games ahead of us,” Olmo concluded. “No one is going to give us anything. We’ve been telling our girls that our first goal was winning (VOL) and (winning section) is our next goal.”

Walljasper finished with eight strikeouts in her five innings of work. Wilson finished with two strikeouts and had a 1-2-3 seventh to end the contest.

“Not a lot of people expected us to compete with Sierra,” Los Banos head coach Dustin Caropreso said. “Allie is by far the best we’ve seen. If we made some plays and didn’t throw a couple of balls away…who knows what happens. I’m proud of how we battled.

“(Sierra) is a good team and they have a very good chance to win this (tournament).”

The T’Wolves will face VOL rival Kimball on Friday at 5 p.m. in the semifinal. If they win, they will play in the final on Saturday at 11 a.m. If they lose Sierra will play again at 7 p.m. on Friday against the winner of Ceres and Cosumnes Oaks, who eliminated Oakdale in the opening round Wednesday.