The pictures showed Liverpool's goalkeeping coach armed with rugby tackling pads and doing his best to disturb his student's attempts to claim a high ball slung into the penalty area.
When asked about the drill, Jürgen Klopp described it as 'specific training for goalkeepers in the Premier League' - a tactic that seems to be reaping rewards on the evidence of Karius' increasing confidence in the face of aerial bombardment.
And the Reds' No.1 has now heaped praise upon Achterberg for his meticulous approach to preparing the club's goalkeepers for the challenges that await them each weekend.