But Robertson is mindful coaching philosophies often mutate, depending on what players bring to the park.
"We've had a similar approach to the game and I think he likes to play football in getting the ball down.
"He's trying to get Havelock into Central League but I'm also sure he's trying to develop their younger players to play an attractive and entertaining brand of football so that's what we're expecting," says Robertson, whose squad is back to full strength but suspects he may have some ineligibility issues on running on the park himself.
Greatholder certainly lends credence to Robertson's suspicions.
"We're adaptable so we have a couple of different formations and styles of play and we've already started a lot of work in the season so I'd like to think he doesn't know how we're going to line up and play," says the 38-year-old whose club harbours a desire to gain promotion in Central League.
The Wanderers, under Greatholder in his first season, are undefeated in five Fed League matches but drew 3-3 away against second-placed Wanganui Athletic FC at Wembley Park in the opening round.
Fans will recognise Havelock North in the way they play but how they attack and defend, what they fall back to in transitional moments (press high or drop deep) aren't set in stone.
"I want a side that's able to change throughout the game," he says, revealing he obtains his kicks from keeping rival coaches guessing in a "good game of chess".
Hawke's Bay United player Ethan Dent, former Rovers Central League goalkeeper Shaun Peta and midfielder Jared Bloor, a former member of the defunct Central League Maycenvale United side, form the nucleus of the Havelock North side.
"They are really good bunch of guys and very coachable. Some of them are still a little raw but there's some absolute talent there."
His task is creating an environment where the 15 to 20-plus year-olds can be challenged to acquire a level of mental fortitude that will prepare them for higher echelons.
But he tempers that excitement for them with a dose of fallibility that comes with youth.
Liam Shackleton and Kenny Willox, both 16, exude talent and can score goals but Greatholder appreciates youth equals mistakes when they are injected in the starting XI.
Willox is the younger brother of Bay United/Rovers midfielder Ross Willox.
"We're averaging six goals a game this season, which is phenomenal, but we're conceding a few as well.
"I know they are going to make mistakes so they need to be exposed to a higher level as soon as possible because that's part of my philosophy."
He chuckles at suggestions that if there ever was an opportunity to do the unthinkable against the favourites now is the time considering they are rebuilding in the elite winter league in the Wellington/Central regions.
"Maybe but I'm long in the tooth to know they're still a bit of an animal," he says, realising the Blues are in a transitional phase but they have enough individuals who can hurt his troops.
"I'm conscious of their strengths and their weaknesses so it's my job to get us tactically sound and set up in the right way.
"Hopefully, the players can then execute the plan to go close to beating them."
He doesn't believe they will suffer stage fright in the big sense of occasion but he suspects the Rovers will have to have an off day and the Wanderers a good one for an upset in football's biggest knockout stage.
"I'm also conscious that if we don't get it right the Rovers will have an easy day at the office."
Greatholder says a loss tomorrow will not have an impact on how their Lotto Federation League season will unfold.
His players look like they can cause some damage with the ball but certain behavioural patterns pertaining to game awareness and tactical nous remain foreign when they are devoid of possession.
"I'm exposing them to this because I believe in them and I think you need to make decisions and make mistakes to get better quicker."
The alternative was injecting more match-savvy heads at the expense of youth but he chose not to entertain such thoughts as they embark on a collective journey of accomplishments.
"It's irrelevant really. If we can beat them it'll be a bonus but if we don't we'll continue to get stronger together throughout the season."
Cup ties tend to "draw some flavour" and Greatholder wishes he could play as well but he is resigned to the fact that he's had his days.
Physicality is a given and it'll be another christening for the wide-eyed villagers.
"Bill sets his team up to be kind of champions, if you like, so he'll want to lead in the intensity and aggression stakes so it's up to us to match that and to put our own stamp on the game."
Centreback Robertson was captain under Greatholder in Bay United but the latter was the former's assistant coach with the Rovers in the past two years.
The pair also were Bay United teammates before Greatholder coached the Stirling Sports Premiership side over summer, historically taking the franchise team to their historic maiden playoffs.
"We'll certainly not be approaching this game lightly with CG in charge because they'll be very, very organised and certainly a threat so we're looking forward to the game."
The 32-year-old had a wry smile when he found out they were matched against the villagers although Alexander Electric Napier Marist, from the third-tier Computer Care HB Premiership undefeated leaders, had thrown down the gauntlet to the Blues after beating Gisborne Thistle at Park Island in the preliminary round last month.
He understands the rebuilding Blues will come across somewhat vulnerable compared with their stellar history but proceeding to round two of the cup remains their focus.
"I'm sure Havelock are looking at it, going we're doing really well in our league and they have had an indifferent start to their season so, you know, it's a good opportunity for them."
He isn't going to be drawn into what-ifs on Marist's challenge as coach Jamie Dunning prepares for a 2pm kick off against fifth-placed Fed Leaguers Breakers Red Sox Manawatu at Memorial Park, Palmerston North, today.
Robertson hasn't seen too much of the Wanderers apart from a couple of players and what makes Greatholder tick.
They will do their homework on Havelock but also focus on how the Blues play.
"Although we've had some close losses and things haven't gone our way we've also played well in patches but I'm comfortable at where we are at the moment."
BOTH TEAMS
■ NAPIER CITY ROVERS: 1 Ruben Parker Hanks (GK), 2 Blake Koolen, 5 Matt Bruin, 6 Oliver Coren, 7 Jean-Michel Paulin, 9 Angus Kilkolly, 10 Fahad Rwakarambwe, 11 Jorge Akers, 12 Ethan Ladd, 14 Josh Stevenson (vc), 15 James Hoyle, 16 Danny Wilson, 17 Fergus Neil (c), 18 Ross Willox, 19 Chris McIvor, 20 Charlie Yexley, Kyle Baxter (RGK).
Coach: Bill Robertson.
■ HAVELOCK NORTH WANDERERS: Shaun Peta (GK), Campbell Whitworth, Stefan Kitchen-Nicholson, Kenny Willox, Bjorn Christenson (c), James Barclay, Liam Carrington, Harrison Gregory, Ben Foxall, Jared Bloor, Jackson Ralph, Sam Waddington, Ethan Dent (vc), Liam Shackleton, Andrew Bowden, Will Kimber (RGK).
Coach: Chris Greatholder.
