In each of the past two seasons, Upper St. Clair was the lower-seeded team when it ended Hempfield's season.
Tuesday night, the roles were reversed and the Spartans got revenge.
Hempfield (15-8), the No. 12 seed, led by as much as 20 in the second half and held on for a 65-56 victory against the No. 5 Panthers (14-7) in a Class AAAA first-round game at Bethel Park.
Two seasons ago, the 14th-seeded Panthers beat No. 6 Hempfield in the quarterfinals, and a year ago No. 13 Upper St. Clair beat No. 4 Hempfield in the first round.
But Tuesday, the Spartans led, 35-18, at halftime and held its largest lead at 50-30 with 3:48 left in the third quarter.
Upper St. Clair closed the gap to five, 57-52, with 1:53 left in the game, but got no closer.
Monica Burns led Hempfield with 19 points, while Constance Raftis had 19 for the Panthers.
More Class AAAA
* Fox Chapel 47, Pine-Richland 37: Down by two at halftime, the third-seeded Foxes (18-4) outscored the No. 14 Rams (14-9), 19-5, in the third quarter to pull away for a win at North Hills. Fox Chapel's Erin Mathias scored nine of her game-high 25 points in the third quarter and also finished with 16 rebounds and 8 blocks.
* Bethel Park 36, Seneca Valley 29: Tied going into the fourth quarter, the No. 4 Black Hawks (17-5) pulled away for a win against the No. 13 Raiders (10-13) at Moon. Harper Zimmer led Bethel Park with 11 points.
* Norwin 55, Penn Hills 48: Alayna Gribble scored 18 points to lead the No. 6 Knights (17-5) past the No. 11 Indians (14-9) at Plum. Freshman Desiree Oliver had a game-high 21 points for Penn Hills.
* Greensburg Central Catholic 50, Laurel 43: The third-seeded Centurions (18-4) scored the final seven points to escape with a win against the No. 14 Spartans (13-10) in a first-round game at Fox Chapel. Carolyn Appleby had a game-high 19 points for the Centurions.
* Seton-LaSalle 61, West Shamokin 33: The top-seeded Rebels (19-4) went on a 21-3 run in the second quarter to pull away for an easy win against the Wolves (13-11) at West Allegheny. Shaunay Edmonds led Seton-LaSalle with 11 points.
* Bishop Canevin 45, Beaver 36: The defending WPIAL and PIAA champion Crusaders (18-5), seeded fifth, led by 18 at halftime in a victory against the No. 12 Bobcats (16-7) at Canon-McMillan. Johnie Olkosky led Bishop Canevin with 18 points.
* Burrell 68, Shenango 25: Jessica Cercone led four Burrell players in double figures with 16 points as the No. 2 Bucs (23-0) cruised to a win against Wildcats (13-10) at Plum.
* Neshannock 34, Washington 18: Tayler Grybowski and Madison McHale each scored nine points to lead the fourth-seeded Lancers (22-1) past No. 13 Washington (14-9) at North Hills.
* McGuffey 77, Brentwood 49: Sammie Weiss scored 20 of her 34 points in the second half as the No. 7 Highlanders (20-3) cruised to a victory against No. 10 Brentwood (15-7) at Peters Township.
* Our Lady of the Sacred Heart 49, Fort Cherry 40: Heidi Langhorst had 14 points and 12 rebounds to lead the No. 8 Chargers (16-7) to a win against the ninth-seeded Rangers (15-7) at Fox Chapel.
* Carlynton 56, Mohawk 22: The sixth-seeded Cougars (19-3) got 28 points and six steals from Conor Richardson in a victory against No. 11 Mohawk (17-6) at North Allegheny.