Junior wing guard Ja'Quan Newton led the way with 18 points, including all seven of his team's first-quarter points. He added five rebounds.
John Davis, a 6-foot-4 senior forward, had 11 points, 10 rebounds, 2 steals, 2 blocks, and an assist.
Trailing by 14-7 after one quarter, N-G, which is also looking for its fourth consecutive PIAA Class AAA state title, recovered and outscored the Patriots, 17-3, in the second.
Junior Troy Harper (11 points) scored seven consecutive points to give the Saints a 21-14 advantage. Carroll never threatened from there.
Carroll's only points in the second quarter came on Joe Mostardi's three-pointer with 1 minute, 11 seconds left before intermission.
"We started playing defense in the second quarter," N-G coach Carl Arrigale said. "Everything else flows from that."
In the third quarter, back-to-back treys from Lamarr "Fresh" Kimble put the Saints (19-5) in front by 32-22.
Later in the third, Harper's one-handed slam of a miss electrified the crown and made it 37-27.
For Carroll (19-5), high-leaping sophomore Derrick Jones had 11 points, 9 rebounds, 3 assists, and 2 blocks.
Archbishop Carroll 14 3 10 7 – 34
Neumann-Goretti 7 17 21 12 – 57
AC: Yosef Yacob 9, Ernest Aflakpui 5, Derrick Jones 11, Joe Mostardi 6, Armand Sorrentino 3.
NG: Hanif Sutton 3, Ja'Quan Newton 18, Tony Toplyn 2, John Davis 11, Lamarr Kimble 9, Jamal Custis 1, Troy Harper 11, Vaughan Covington 2.
Contact Rick O'Brien at firstname.lastname@example.org, or follow on Twitter @ozoneinq.