Haddon Heights (18-3-3) will play Harrison in the state championship game at 10 a.m. Saturday at the College of New Jersey.
"I just didn't want to focus on what they were doing and do my own thing," Weaver said. "It was just great. It was awesome."
Weaver wasn't even supposed to take a kick. But when Kevin Nelan went down with a hamstring injury late in the overtime, everyone bumped up a spot and Weaver took a penalty kick for the first time in his career.
"He buries them every day in practice," Garnets coach Jeff Eppright said. "We decided to have him shoot last. We knew if he made [the saves] he was going to bury the opportunity and be the hero."
Weaver, who was also in goal when Haddon Heights advanced to the state final two seasons ago in a shootout, made one save during the penalty kicks.
He dived to his right to deny Feli Csombok, who led South River (19-3-3) with 31 goals this season. Weaver also stopped Csombok on a direct kick from just outside the box to preserve a 2-2 tie.
Neither team scored after halftime.
Weaver is determined that his final trip to the state-title game won't end in a loss as it did two years ago.
"I'm ready to win it this year," Weaver said.
South River 2 0 0 0 – 2
Haddon Heights 2 0 0 0 – 2
(Haddon Heights wins, 5-4, on penalty kicks.)
Goals: SR-Obeth Silva, Rolando Martinez; HH-Andrew Hicks, Jesse Weick.
Saves: SR-Getsamani Lopez 6; HH-Jon Weaver 9.
Contact Tim McManus at tmcmanus@philly.com, or follow on Twitter @ByTimMcManus.