It is the undercurrent or subplot to an NFL or major college football game almost every week: Teacher versus student.

Assistant coaches grow under the tutelage of a wise, veteran coach, become students of the game and move on to hang their own shingle over a program. And of course they achieve varying degrees of success, although usually the instructor delivers another lesson or two before the ex-understudy turns it around in his new environment.

That hasn’t been the case in the Class D South coaching battle between Stacen Doucette of Oak Hill and Dick Mynahan of Lisbon.

Perhaps it is a statistical anomaly, and maybe there were some extenuating circumstances and good, old-fashioned friendly bounces involved, but protégé Doucette and his Raiders are 6-0 against mentor Mynahan and his Greyhounds since the two first stood on opposite sidelines in 2012.

Oak Hill has swept the scheduled game and playoff rematch from Lisbon every season. In each of the past two years, the Raiders have gone to win the state title.

The Route 9 rivalry continues at 1:30 p.m. Saturday in Wales, with undefeated Oak Hill (5-0) hosting stingy Lisbon (3-1) in what promises to be another close, emotional, hard-hitting tussle.

Lisbon hasn’t backed down from Oak Hill in any sense of the word. The playoffs were a one-point game in both 2013 (21-20) and 2014 (7-6). Both 2012 contests were decided by a touchdown.

Saturday’s game is perhaps the final major obstacle between Oak Hill and home field advantage throughout the Class D South playoffs. The Raiders already have beaten Dirigo, 20-14, and Winthrop/Monmouth, 28-19.

Dalton Therrien has emerged as one of the most dangerous players in the conference. The senior scored rushing touchdowns from both the quarterback and wingback positions and threw for another score in last week’s win over the Ramblers.

Oak Hill has enjoyed its usual one-two punch out of the backfield, with Levi Buteau and Cruz Poirier getting tough yards between the tackles. Jonah Martin and Connor Nilsson’s hands spark the aerial attack.

Garrett Gile, Brendon Tervo, Brian Thorpe, Martin and Buteau lead the defense.

Defense has been Lisbon’s calling card this season, with takeaways a deciding factor in each win. Lisbon forced four turnovers against Winthop/Monmouth (14-7) and three against Boothbay (19-0) Tyler Halls had a long interception return for a touchdown to provide the winning points in a 13-6 verdict over Old Orchard Beach.

The lone loss was a 21-14 decision against Dirigo. Lisbon scored two fourth-quarter touchdowns to throw a scare into the Cougars.

Lisbon also has produced three goal-line stands, a tradition that will remind longtime fans of the glory days in which the Greyhounds won Class C state championships in 1997, 2005 and 2006. Doucette was an assistant coach in those years.

Halls’ elusiveness and two reliable targets in Henry Adams and Tyrese Joseph make him a dual threat at quarterback. Bruising fullback Noah Francis provides the tough yards inside.

The Greyhounds seek their first win in the series since 2011, when they won 24-14. 

koakes@sunjournal.com