Meghan Wallace stood at the edge of the penalty area in stunned disbelief — hands atop her head, mouth agape.

Believe it, kid.

One year after being on the wrong end of a shocking playoff result, East Union delivered one of its own during a 3-2 victory in the opening round of the Sac-Joaquin Section Division IV tournament on Thursday.

Wallace volleyed the game-winning goal over the head of Foothill goalie Liz Daner with 2 minutes, 34 seconds left, saving the top-seeded Lancers from a near-disastrous second-half performance.

East Union (20-1-2) led 2-0 when the game — and its season — nearly went sideways.

Foothill (6-9-2), a sub-.500 team and the third-place qualifier out of the Pioneer Valley League, scored on back-to-back shots midway through the second half to tie the game and unravel the Lancers.

“We knew we were playing against an excellent, experienced side,” Foothill coach Harley Sauvage said. “Our game is blood and guts. We fight for every 50-50 ball and we play with heart. When we got that first goal, it gave us confidence.”

Wallace stymied the rally with a picture-perfect goal.

“What a shot. What a finish,” Sauvage said. “She got some space and wheeled one in.”

Wallace’s 12th goal of the season saved East Union from certain overtime and the possibility of a penalty kick shootout for a second consecutive year. The Lancers were eliminated by Central Catholic in PKs last spring, 3-2.

“I feel like we lost our focus. We were a little overconfident,” Wallace said. “It was intense out there. I’m glad we calmed down.”

Marissa King and Erica daSilva also notched goals for East Union, which hosts Colfax on Wednesday in a semifinal contest. The Lancers have never advanced to a section final, much less raised a blue banner.

“The girls asked us, ‘Do you think you can put up with us for a few more days?’” head coach Jim Todd said, nodding to assistant Juan Sandoval. “We said, ‘Gladly, let’s do this.’ “

As the final seconds ticked away, the East Union sideline, silenced and heart-broken following a stunning first-round loss a year ago, readied itself for celebration.

The reserves linked arms and danced along the sideline, tickled by the anticipation of the final whistle. When it finally sounded, they charged the field, swallowing up Wallace before breaking out in a bounce.

“What was exciting was seeing the girls lined up,” Todd said. “Everybody is in this for the team. As a team, they said this wasn’t going to be their last game.”

The magic was provided by the one Todd calls “Gumby” for her physicality, range and ability to win virtually every ball.

That certainly was the case on the game-winner.

Wallace used her head to flick a ball pushed up the sideline by defender Kianna Lamont, who was slowed by an ankle injury late in the first half.

The junior charged onto the bouncing ball — beating two Mustang defenders — and uncorked a volley from just inside the right corner of the penalty area.

Her shot froze Daner (10 saves), who stood flat-footed and beaten as the ball slipped into the far corner with 2 1/2 minutes remaining.

It took a second for the game-winning goal to register with Wallace.

“I thought it was going over,” she said. “I’m just excited. We didn’t want our season to end.”

East Union displayed the poise and passing ability of a No. 1 seed, but its inability to finish off Foothill nearly cost it dearly.

The Lancers outshot the Mustangs 26-4, including 14-0 in the first half. Foothill’s only offensive thrust in the first half was a cornerkick and it didn’t get off its first shot until the 53-minute mark.

But the Mustangs’ Vicky Millan made it count. She dribbled two defenders and poked a goal past the stretch of Adrienna Wood (two saves) to make it 2-1.

Ten minutes later, Wood was victimized by a bad bounce.

The sophomore made a reaching save on a tall shot by Julia Herrera. The ball caromed off the crossbar, and with Wood on the ground, bounced off the goal line and spun into the net to tie the game.

It was the first time Wood -- who has split time with senior Ashley Almeida all season -- has given up two goals in a game.

“She’ll pick herself up,” Todd said.

King gave East Union the early lead with a curling shot in the third minute. King controlled a centering pass from Madeline Yslava near the PK stripe and flipped it into the left panel.

The score remained 1-0 at the half despite an overwhelming shot and possession advantage for the Lancers.

“I think it was the nerves of such a big game. I think it got to us a little bit,” Wallace said of the team’s inability to finish. “Hopefully in the next game we’ll execute better.”

daSilva, who banged a shot off the crossbar from 45 yards out in the first half, stretched the lead to 2-0 in the 48th minute.