Having a game plan to counter Suburbs' possession-based game and executing it "to perfection today" he felt culminated in that don't-argue statement.
However, in some respects the yawning score line didn't do the game or the visitors justice.
The Declan Edge-coached Reds showed dazzling speed and skills all over the park but didn't have the mental fortitude to find the net when it mattered.
The ease, at times, with which they dissected the Rovers' defence made it an exciting spectacle for the Bluewater Stadium faithful.
"We knew they play that way so we've done some research on that and come away with a plan to combat that," Robertson said, adding the Blues had dominated in possession to create some problems to score goals.
The visitors butchered two scoring chances in a hiss-and-roar start but the Danny Wilson-captained Rovers went up 1-0 in the ninth minute from a penalty kick from striker Angus Kilkolly after a defender brought down Miles John in the box.
Seven minutes later the Blues extended the lead to 2-0 from midfielder Saul Halpin in what can best be described as a team goal with a flurry of money-ball passes in the stock exchange.
The floodgates opened in the 20th minute when Suburbs goalkeeper Andrew Withers appeared to pull out as he saw the imposing form of Josh Stevenson charging in. The left winger prevailed, 3-0.
The Wellingtonians then survived waves of attacks with Withers denying centre-mid Tom Biss who simply needed to push it past the keeper on his left but got a little cute.
In the 26th minute Suburbs centre-mid Ben Sippola pulled one back, 3-1. He seemed to have all the time and space in the world inside the box to drill it past Rovers gloveman Ruben Parker Hanks.
Two minutes after halftime the hosts went up 4-1 from a Kilkolly header off a Stevenson corner kick following a Suburbs defensive blunder.
Midfielder Ryan Tinsley made it 5-1 after a cross from Stevenson to ensure he kept Kilkolly in check in the golden-boot race in the 61st minute.
Sippola was the lifeblood of the Surburbs' engine room. Edge said that was expected of the more experienced midfielder.
The ex-All White said he had brought the Waikato side here before and lost by similar margins but from that group four had turned professional.
"This group is just as good if not better than that group," he said, keen to compete in the league and happy with second place.
"But we're in the business of producing young New Zealand footballers like Noah Billingsley who is the pin-up boy for the national under-20s."
Edge said he was on a "different project" in a winning mentality versus producing talent for national teams and to become professionals.
"We give all credit to Napier and they are different [from] us," he said, revealing half a dozen of his squad were just 16.
"I keep telling people in Napier I have four players who are professionals in Italy, Holland, Portugal and South Africa," he said, adding six were in the United States.
"So we take the losses as part of the learning process."
While disappointed to lose, he was confident up to five would become professionals.
"There'll be none from Napier, I can predict that now," he said, adding the club here had provided a stellar day and facility, although some sections of the crowd could have been better.
The Blues play Stop Out away this weekend before hosting Miramar Rangers at home the next round. They travel away for a Chatham Cup game against Palmerston North Marist after that.
