It was the second time in recent weeks that the Dons, who have been finding tries hard to come by at times, have failed to score.
As was the case in the 52-0 defeat against Toulouse, the Dons attack rarely clicked into gear and in-form Knights had few problems putting them to the sword as they avenged an opening day defeat at the Eco-Power Stadium.
The Dons badly missed the power of the suspended Pauli Pauli in the forwards but it is unlikely that had he played it would have changed the result against a side which has now won six of its last eight games.