Isiah Parker scored 16 of his 26 points in the second half for Seton Catholic, but the Cougars rally fell short on the road in Everett.
Seton (2-6) had a shot to tie the game at the buzzer, but it went in-and-out.
Henry Demsky was also in double figures for the Cougars with 14 points.
ARCHBISHOP MURPHY 66, SETON CATHOLIC 63
SETON CATHOLIC (2-6) — Henry Demsky 14, Isaiah Parker 26, Matthew Kent 13, Luke Pitzer 0, Hayden Miller 4, Topher Strong 0, Chris Dumas 0, Delano Morgan, Malik Williams 3, Sam Jackson 0, Andrew Olson 4, Zach Cowger 0. Totals 15 (7) 12-17 63.
ARCHBISHOP MURPHY — Cole Calnon 5, Jaxon Miller 1, Trey Miller 27, Jeric Williams 0, Rewhabura Munyagi 11, Dillon Halpin 6, Mateo Trimble 0, Eric LaMarre 3, Sage Oliveria 2, Nolan Chin 4, Ryan Kenny 3, Colin Guy 0, Alex Peterson 3. Totals 27 (6) 6-10 66.
