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In the quarter-finals, the match-ups were as follows
Quarter-final 1: First-placed team in Division One v First-placed team in Division Three (South)
Quarter-final 2: Second-placed team in Division One v First-placed team in Division Three (North)
Quarter-final 3: Third-placed team in Division One v Second-placed team in Division Two
Quarter-final 4: Fourth-placed team in Division One v First-placed team in Division Two
The semi-final match-ups are
Semi-final 1: Winner Quarter-final 1 v Winner Quarter-final 4
Semi-final 2: Winner Quarter-final 2 v Winner Quarter-final 3
The final match-up is: Winner Semi-final 1 v Winner Semi-final 2.
Promotion and relegation
Owing to the re-structure of the league, promotion and relegation did not take place in the same manner as it did under the same structure in other years.
Division One: No relegation. All 8 teams placed in Division One of the 1991–92 NFL.
Division Two: top 7 teams placed in Division One of the 1991–92 NFL. Bottom team placed in Division Two of the 1991–92 NFL.
Division Three (North): group winners promoted to Division One of the 1991–92 NFL. Group runners up play-off for the third promotion slot from Division Three to Division One of the 1991–92 NFL. Remaining teams in the group placed in Division Two of the 1991–92 NFL.
Division Three (South): group winners promoted to Division One of the 1991–92 NFL. Group runners up play-off for the third promotion slot from Division Three to Division One of the 1991–92 NFL. Remaining teams in the group placed in Division Two of the 1991–92 NFL.
Separation of teams on equal points
In the event that teams finish on equal points, then a play-off will be used to determine group placings if necessary, i.e. where to decide relegation places or quarter-finalists.