WHITEHALL — Needing a spark in the first set, Seneca Valley girls volleyball coach Karen Martini turned to her bench and to Katie Whittle.

Whittle served nine straight points to get the Raiders going and on their way to a 3-1 win over Hempfield in the WPIAL Quad-A semifinals Thursday night at Baldwin High School.

“She was a game-changer for us,” Martini said. “Our bench is so deep and as a coach I'm confident in each player.”

Seneca Valley also got a big night from what Martini calls her “Big 5”: Maria Alfano, Tatum Poirier, Emily Devlin, Maddie McDonough and Bella Seman.

Alfano, Poirier and Devlin divvied up the kills, which were set to them by McDonough.

“When McDonough gets hot, our hitters are almost unstoppable,” Martini said. “She really dispersed the ball around the net. She was on fire.”

Seman also had a strong game at libero.

“When the other team serves, I'm always like, 'Please serve the ball to Bella. Please serve the ball to Bella,'” Martini said. “She gets everything going.”

Now Seneca Valley is going to the WPIAL final.

In the last two seasons the Raiders lost in the WPIAL semifinals, first to Baldwin in 2014 and then to North Allegheny last season in closely contested games.

This year, after dropping the second set to Hempfield, the Raiders cruised.

Poirier also provided the Raiders a spark when Seneca Valley was down after the second-set loss.

“She turned around and looked at the girls and said, 'We're not doing this anymore,'” Martini said. “She just has a fire.”

Seneca Valley will play Baldwin, which swept Bethel Park 3-0 in the other semifinal, Saturday at 6 p.m. at Baldwin.

“I think the pressure is off for them,” Martini said. “If you can keep them focused and calm and play at their tempo, they will be OK.”