Barrett made 14 stops on 19 shots on goal to lead the Friars to an 11-5 win in a game with huge implications in the Inter-Ac League.
With a win, the Churchmen could have clinched at least a share of their first Inter-Ac regular-season title since 1998. But now Malvern Prep and Haverford School are still in the hunt.
Malvern Prep coach John McEvoy thought Barrett's injury would leave him sidelined for a significant amount of time, but Barrett has played in every lacrosse game this season.
"It's like it never happened," McEvoy said. "He's like [NFL running back] Adrian Peterson."
The Friars jumped on the Churchmen early, scoring on each of their first three shots. Less than three minutes into the first quarter, Malvern Prep held a three-goal lead.
Episcopal cut the margin to 5-2 by halftime, but struggled to get the ball past Barrett in the second half.
"The defense played really well," Barrett said. "All the shots I saw, I felt that the defense was doing a good job in front of me."
Malvern Prep, ranked No. 2 in the area by phillylacrosse.com, improved to 12-4 overall and 6-1 in the Inter-Ac. Episcopal, ranked No. 1, dropped to 13-4 and 7-1.
The Inter-Ac regular season will wrap up next week.
"It doesn't matter who you're playing - if you're in the Inter-Ac and you have more than one loss, you're not going to win it," McEvoy said. "And it's really tough to go undefeated in the Inter-Ac."
Episcopal Academy 1 1 2 1 – 5
Malvern Prep 4 1 3 3 – 11
Goals: EA: Tyler Chambers, Peter Gayhardt, Trupert Ortlieb 2, Curtis Zappala; MP-Joe Dunn 2, Conor Glancy, Chris Hillburn 2, Kevin McGeary, Eddie McLoughlin, Tommy O'Connor 2, Joe Carlini 2.
Saves: EA-Colin Reder 10; MP-Matt Barrett 14.
Contact Joey Cranney at JCranney@Philly.com. Follow on Twitter @joey_cranney.