"He's a patient player," Church Farm coach Marc Turner said. "He understood we weren't going to give him the driving lanes. He did what a great guard does, which is look for the open guy."
Amir Butler, a 6-2 senior forward, paced the Cougars (22-8) with 17 points. Mattox drained four first-half threes and scored 14 points.
"At the beginning of the year, I was making a lot of threes," Mattox said. "Before this, I was in a slump. My shot is starting to fall again."
Tuesday, at a neutral site and time to be determined, Vaux will clash with Math, Civics & Sciences in a semifinal. The Mighty Elephants played poorly but eliminated Sankofa Freedom Academy, 71-59, in the first game at La Salle.
Vaux, ranked No. 5 in Southeastern Pennsylvania by The Inquirer, and No. 6 MC&S split meetings during the season. The winner of the rubber match will punch a ticket to Hershey.
"I'm anxious for the rematch," Butler said. "We just have to play hard and do the things we did last time."
The Cougars prevailed, 62-61, last month in the Public League Class A championship game.
Against Church Farm, Vaux led by as many as 17 in the first half and were in front, 41-25, at the break. Mattox nailed four threes in the first 11 minutes.
Junior guard Tyler Ofray paced the Griffins (24-7) with 17 points, including four threes. Mlynue Reeves, a 6-7 senior forward, was next with 10.
Vaux 14 27 8 19 - 68
Church Farm 15 10 13 26 - 64
V: Rysheed Jordan 9, Amir Butler 17, Trayvond Massenberg 9, Lester Mattox 14, Sammy Foreman 7, Karon Snead 6, Daron Johnson 6.
CF: Aondofa Anyam 2, Michael Mohamed 5, Larry Cermak 10, Jan Bohm 6, Joey Shelton 3, Tyler Ofray 17, John Rodriguez 8, Mlynue Reeves 13.
Contact Rick O'Brien
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