It came after a week of goading from National over the Government's policy to encourage the use of electric and hybrid vehicles, which included a series of social media advertisements aimed squarely at Green Minister Julie-Anne Genter.
The Greens, unwisely, took the bait and responded with an advertisement of their own, which mocked National leader Simon Bridges' stance on electric vehicles and used a voiceover with a very broad New Zealand accent.
This is almost exactly what Mr Bridges would have wanted to happen; by laughing it off, as he did, it made him seem like a reasonable person who is able to take a joke . . . and also gave more publicity to National's campaign.
But it got even better for National just hours later, when the Greens withdrew the advertisement and apologised for it being "poor taste" and lowering the tone of the debate.
Once more, it gave National another chance for its attack line to be run, and at the same time undermined any defence the Greens might advance.
At best this kerfuffle made the Greens look humourless, at worst it made them look divided and lacking the assertiveness to fight their corner.
Even worse, in the long term it may well have hamstrung their entire 2020 campaign: who would want to be the advertising agency pitching a strategy to a party willing to second-guess and reverse itself so readily?
As personal mockery of politicians by politicians goes this was hardly the most egregious example ever seen.
Given its relatively benign nature, it is unlikely in itself to signal an election campaign full of muckracking.
What is does highlight though is, as all parties already know, the vital importance of social media as a political battleground.
It also demonstrates the fine line between a thumbs up and a laugh emoji and a thumbs down or an angry face.
If there was a custard pie in the face emoji, the Greens just got one.
