On Tuesday, Riverview (19-3) visits District 5 champion Conemaugh Township (19-1), while Springdale (14-4) travels to Seneca High School in Erie for a two-hour game against the District 10 champion Bobcats (17-0).
The teams each won one game in the regular season and tied 3-2 in the WPIAL semifinals.
Raiders coach Sean Abraham and Dynamo coach Marc Bentley said their teams aren't looking forward to a possible rematch because they know they'll have their hands full once they arrive at their respective tournament sites on long bus rides.
"It's great to see them again on Saturday, but we can't help but focus on what's in front of us," Bentley said.
"We want to play well and win tomorrow and then look ahead to the next round.
Riverview is looking to avenge a tough 1-0 loss to Freedom in Friday's WPIAL tournament at Highmark Stadium for Tuesday's game.
Tuesday's game is the Raiders' first PIAA playoff game.
Abraham said, "I felt like we dominated possession for most of (the WPIAL championship game). There was only one unlucky bounce where the ball got through.
"We had a practice (Sunday) and the guys were in high spirits. We talked about some of the things we did wrong against Liberty and some of the mental disappointments we had in the game. They know they have a great shot at the state tournament.
Springdale is looking to build on last Thursday's 7-0 thrashing of South Allegheny in the WPIAL quarterfinals.
The Dynamo look to end their undefeated season with a win over the Bobcats on Saturday.
Briana Ross has scored 46 goals for the Dynamo this season and is the PIAA Class A scoring leader this season.
Seneca's defensemen have only scored four goals all season.
They have a lot of talent and we expect it to be a tough game," Bentley said.
Bentley said, "(Pikevich) is a strong player for them, but it takes more than one player to go undefeated like they have. We know they are strong overall. It's going to be a good challenge to play a new team and we're looking forward to it.
Both teams are looking to win Tuesday's game and meet again in the second round on Saturday afternoon.