WHEN is a local derby not a local derby? You’d think I’d know by now.

Working in the footballing hotbed of the North West, you are never far from a heated sporting discussion and this week I struck upon a doozy.

Monday night’s victory over Bury was the first Wanderers had achieved in the league at Gigg Lane in 87 years; an undeniable fact.

As quite a few fans correctly pointed out, the two clubs have not played at the same level for most of that period. This is just the 16th season Bolton and Bury have been in the same division since 1929.

The statistic was valid enough to impress Phil Parkinson, who used it quite extensively in his pre-match press as a motivational tool for his players. Judging by the result, he got it spot-on.

Unfortunately, that might not have been the case for yours truly. My description of Bury as ‘local rivals’ or the match itself as ‘a derby’ seems to have rankled some of the traditionalists.

It has also raised an age-old argument on our sports desk about which team really are Wanderers’ arch-nemesis.

My theory is simple. A derby should first of all be judged by geography, i.e. the nearer the better. There are some, Ipswich and Norwich for example, who have no other choice but to look further afield for a real rival. Those two cities are an hour’s drive from each other on a good day.

Bury’s town centre is six miles away from that of Bolton. The fixture ticks that particular criteria.

Oldham and Rochdale are easily reached too, yet provoke nothing like the response from Wanderers supporters and recent games against them felt rather flat in comparison with Monday night.

That is where tradition must be factored in. The game must have been played for long enough and at a suitably high standard to matter.

Wigan Athletic are relative newcomers to the Football League scene and didn’t play Wanderers in a competitive fixture until 1983. It has taken some time for that game to really spark – but the two neighbouring towns now share enough common ground, in my view at least, to be considered rivals.

Preston North End are slightly further afield but also fall into the traditional enemy bracket.

The same goes for Blackburn Rovers. There is a long history of games against our friends from Ewood Park but that pairing falls slightly flat in the third and final part of my derby theory.

I think the rivalry must be reciprocal.

If you believe the song, Wanderers fans “only hate Man United,” and there is no question a victory over the Reds is savoured more than any other.

Without being disrespectful, there is rarely a mention of Bolton on the terraces at Old Trafford. United have City to worry about – and the two Mancunian giants rarely give anyone else a second thought.

Likewise, Rovers. Burnley occupy the most tribal of their fans’ thoughts and though games against Wanderers will always have a bit of spice to them, it will never be “The” derby to them.

I have been lucky enough to work on both sides of the fence with Bolton and Bury, covering both clubs. I can safely vouch for the rivalry on the Gigg side and still get texts from Shakers-supporting friends revelling in the Whites’ misfortunes.

Sitting in the Main Stand at Bury, watching 3,000-plus Wanderers fans going nuts as Phil Parkinson’s side chalked up a fifth successive win, I could have sworn I sensed some local rivalry brewing. Evidently not, if you read some of the correspondence I have had since.

I’ve come to the conclusion that local rivalries are organic. They ebb and flow with time and success. Those who remember great tussles with Manchester United on an equal par are much less likely to accept Bury as an acceptable substitute.

What is important to Wanderers is that the level of support remains as good as it has been this season, regardless of the opposition. The numbers, home and away, have been quite phenomenal.

I still tip my cap to each and every person who follows their team each weekend having been through the trials and tribulations of the last 12 months. Success, I hope, will be all the sweeter.