Newton, a Miami signee, netted 15 points. Jamal Custis (10), Troy Harper (nine), and reserve Vaughn Covington (nine) combined for 28.
Derrick Jones, the Patriots' junior star, was held without a field goal in the second half and finished with 11 points. He scored his 1,000th career point on a fourth-quarter free throw.
At 8:30 p.m. Monday, back at the Palestra, N-G will face Roman Catholic for the Catholic League crown. The Cahillites advanced earlier with a 52-45 victory over La Salle.
Early in the fourth quarter, sophomore guard Vaughn Covington's three-pointer and senior forward Jamal Custis' fastbreak layup put Neumann-Goretti in control at 50-42.
At the end of the third stanza, Newton's three-pointer from the left wing put the Saints, who came in ranked No. 2 in Southeastern Pennsylvania by The Inquirer, ahead by 45-40. On that shot, he became the program's all-time leading scorer. He has 1,816 points.
Back in the second quarter, the Saints had put together a 7-0 run to go ahead, 24-16. The spree featured Newton's three from the right wing.
The No. 3-ranked Patriots responded with an 8-0 run to tie the score. It consisted of Derrick Jones' follow, Austin Tilghman's drive, Jones' inside bucket, and Ernest Aflakpui's bank shot from the lane.
The Saints closed the first half with a 5-0 run, capped by Covington's three-pointer, for a 29-24 lead.
For Carroll (20-4) in the first half, Aflakpui (eight points), Jones (six), and Tilghman (six) combined for 20 points.
Neumann-Goretti (20-4) was sparked before halftime by Covington (six points), Custis (six), Newton (five), and Harper (five).
Archbishop Carroll 14 10 16 22 – 62
Neumann-Goretti 14 15 16 22 – 67
AC: Joe Mostardi 5, Ernest Aflakpui 14, Derrick Jones 11, Austin Tilghman 11, Samir Taylor 14, David Beatty 5, Josh Sharkey 2.
NG: Lamarr Kimble 17, Troy Harper 9, Tony Toplyn 4, Jamal Custis 10, Ja'Quan Newton 15, Quade Green 3, Vaughn Covington 9.