There are several issues here. First and foremost, it sounds like the back end of a league home-and-home. Neither coach gets to "schedule" the opponent; it's scheduled for them. Still, knowing the likelihood of a rout, BOTH coaches should endeavor to avoid same: the Pinewood coach by substituting early and often and emphasizing elements OTHER than scoring, and the Northwood coach by doing a better job preparing his/her team.
One thing I will say here: If the Pinewood coach had any more starters than necessary on the field in the second half, he/she is a fool. Seeing anyone injured during a rout hurts. Seeing a key starter injured while trying to roll up a score is, in my mind, a firing offense.