The Shaler Area girls' softball team chipped away, scoring single runs in the third, fourth and sixth innings to earn a 5-1 victory against Trinity (12-7) at Fairhaven Park in a WPIAL Class AAAA quarterfinal matchup yesterday.

Shaler (15-4) used solo home runs from Chelsea Siar in the third and Stevie Stanek in the sixth, and also got two RBIs from Jenna Conrad.

Megan Daley earned the pitching victory, striking out six and yielding six hits.

The Titans' victory sets up a semifinal matchup against Section 3 foe Seneca Valley. Shaler lost twice against Seneca Valley in section play this season.

"We have been battling Seneca Valley for years," Shaler coach Skip Palmer said. "Neither team is going to surprise the other."

More Class AAAA

• Mt Lebanon 2, North Hills 1: Sarah Mervosh and Kathleen Mathison had RBI singles in the fourth, and Geena Badolato tossed a two-hitter, to lift Mt. Lebanon (17-3) to a narrow victory against North Hills (11-6) at Fairhaven Park. North Hills scored in the seventh on a sacrifice fly by Ally Gross.

• Seneca Valley 10, Kiski Area 2: The Raiders (15-5) pounded out 13 hits, led by Dana Hughes, who went 3 for 5 with three RBIs, in a lopsided win against Kiski Area (13-6) at North Allegheny. Courtney Grootegoed tossed a four-hitter to get the victory.

Class AAA

• Ellwood City 5, Chartiers Valley 4: In nine innings, the Wolverines (17-1), who made five errors, earned the narrow win against Chartiers Valley (14-8) at North Allegheny. Kaycee Bradosky scored from second base on a two-out single by Ciera Damon in the bottom of the ninth for the winning run. Damon also hit a solo home run in the seventh to send it to extra innings.

• Elizabeth Forward 7, Ambridge 3: The Warriors (15-5) used 12 hits and pitcher Kristen Hawkins threw a four-hitter and also went 4 for 4 in a victory against Ambridge (12-9) at Fairhaven Park. Hilary Holets and Brittany Bruce each had two RBIs for Elizabeth Forward.

• Montour 1, Waynesburg 0: Montour (16-6) made a run in the first hold up in a win against Waynesburg (13-5) at California University. In the first, Sarah Capp had an RBI single that scored Marina Scarantino for the lone run. Capp also starred on the mound, tossing the two-hit shutout.

• Belle Vernon 4, Indiana 2: Apryl Patterson's fifth-inning grand slam provided all the runs defending WPIAL champion Belle Vernon (14-7) needed in a win against Indiana (12-8) at California University.

Class AA

• Washington 3, Valley 2: Defending WPIAL champion Valley (14-2) fell in eight innings as Jenna Phillips had a walk-off double for the Little Prexies (19-3) that chased home Jordan Jackson at California University. Alexis Lopez had a leadoff home run in the first for Washington.

• South Park 5, Sto-Rox 0: Lindsay Harkins tossed a two-hit shutout to lead South Park (15-5) past Sto-Rox (12-4) at Finley Middle School. Jessica Morgan went 2 for 4 with two RBIs, and Nicole Doria had an RBI to lead the Eagles.

Class A

• Avonworth 4, Bentworth 2: Avonworth (12-8) scored all its runs in the third inning at Finley Middle School to slip past Bentworth (14-7). Avonworth is in the postseason for the first time since 1977.

• Mount Alvernia 2, Neshannock 1: Pitcher Lisa Kaczynski, also a stellar basketball player, struck out 11 batters to lift Mount Alvernia (13-5) to the victory against Neshannock (17-3) at Hampton. Jennifer Lentz and Lauren Sauerwein had RBIs for the Lions.

• Leechburg 7, Fort Cherry 1: Fort Cherry (14-4) scored first, but then Leechburg (14-3) used a four-run third inning to beak the game open and cruise to the win at Hampton. Keli Barnes went 2 for 3 with two RBIs for the Blue Devils.

City League quarterfinals

• Schenley 3, Langley 2: The visiting Spartans (7-9) got all three runs in the first and held on for the victory against the Mustangs (12-5). Ellie Tecza had two RBIs for Schenley.

• Brashear 7, Allderdice 0: The Bulls (9-5) had an easy time with Allderdice (10-8) at Langley, as pitcher Brandi Piccolino threw a one-hitter with 13 strikeouts.