Grange manager Martin Shepherdson believed the scoreline was not a fair reflection of the game.
He said: "Our effort in the first-half was outstanding. Their set-piece was very impressive and we were pleased we made them work hard for their victory. We now look forward to a tough game against Hampstead & Westminster."
The Ducks, who were the first Belgian team to win the EuroHockey League in 2019, were made to work hard for the breakthrough, but then rammed home eight unanswered goals, three coming in six confidence-sapping minutes.
Three more followed in two minutes near half-time and a tiring Grange side lost another couple in the last two minutes.
Big, bustling forward Victor Charlet claimed four, all from penalty corners, and William Ghislain two field goals late on in the rout, but Grange's Albert Rowley did hit the frame of the Ducks’ goal late on.
The Edinburgh side now meet London-based Hampstead & Westminster, champions of England in 2019, in their next game on Saturday after they drew 3-3 in regulation time with German Division One side Mannheimer but then lost 5-4 in the shootout.