All the parts added up for the Upper St. Clair girls' basketball team last night:

• A suffocating defense against one of the WPIAL's top shooters.

• A two-pronged offensive effort by Andrea Pion, who scored 18 points, and Alex Gensler, who netted 15.

• A late-game defensive stand.

Together, the result for the Panthers (21-5) was a 49-46 victory against Oakland Catholic (16-11) in a WPIAL Class AAAA semifinal at Chartiers Valley.

Upper St. Clair advanced to the WPIAL championship Saturday when the Panthers will face Peters Township. Upper St. Clair, which last won a WPIAL title in the 2002-03 season, broke an Oakland Catholic streak of reaching the championship for nine consecutive seasons.

In the early going, it looked as if Upper St. Clair would run away from Oakland Catholic.

Upper St. Clair played at an up-and-down pace and took a 16-8 lead after the first quarter partly because of that running style, but Oakland Catholic didn't do itself any favors in the first eight minutes, either.

The Eagles shot 2 of 14 from the field in the first quarter and turned the ball over seven times during that stretch. Upper St. Clair turned that advantage into a 26-18 halftime lead as the game slowed slightly.

Oakland Catholic junior sharpshooter Colleen Kiss, one of the best long-range threats in the WPIAL, scored just one basket -- a 3-pointer with 1:33 remaining in the game. She came in averaging more than 15 points per game, but Upper St. Clair's Meghan McLean hounded Kiss wherever she went, denying her the basketball from baseline to baseline.

"They did a good job on Colleen. Even when they missed and we were pushing the ball up the court in transition, they seemed to always find her," Oakland Catholic coach Chris Walker said of Kiss, who finished 1 of 8 from the field.

Oakland Catholic, led by Blair Cotton's 14 points, stormed back through the heart of the third quarter and early in the fourth, taking a 43-41 lead with 5:05 left.

But the Panthers closed on an 8-3 run, holding off three Oakland Catholic chances at a tie in the final 31 seconds when a disorganized Eagles offense had to call two timeouts and then settle for a 30-foot attempt at the buzzer.

Other semifinal

Peters Township (20-7) clawed back from an 11-point deficit in the final minutes of the third quarter to claim a 41-37 victory against No. 1 seed Mt. Lebanon (24-3) at Canon-McMillan.

Emily Correal led the Indians with 16 points and eight rebounds. She hit a driving layup with 51 seconds left to give the Indians a 39-37 lead that they wouldn't relinquish.

Mt. Lebanon, which played without coach Dori Oldaker for the second consecutive game because of childbirth last week, didn't have a player in double figures. The Blue Devils were led by Jackie Babe's 9 points.

In the fourth quarter, Mt. Lebanon was held to 1-of-12 shooting from the field and was outscored, 18-7, while Peters Township went 6 of 10 from the floor in that span.