Pirates maintained their dominance over the Castle Park side when completing another league double with a bonus point 27-10 victory at windswept Mennaye Field where Knights haven’t won since 2016.
It was always going to be a big ask for a much-changed Doncaster side who added another couple of names to their long injury-list when claiming back-to-back home wins against London Scottish.
In addition to the starting debut of loan signing Guido Volpi, Bath second-rower Will Britton was promoted from the bench when in-form flanker Wian Conradie fell ill.
Knights had first use of the blustery, swirling wind and fly-half Sam Olver made good use with a long-range penalty on eight minutes to give his side a 3-0 lead.
Pirates hit back on 13 minutes. An attempted clearance kick was charged down which led to centre Callum Patterson going over in the corner too far out for fly-half Jarvier Rojas Alverez to convert.
Patterson went in at the corner for a second unconverted try to make it 10-3 before wing Alex O’Meara cut inside between two defenders and then rounded Hayes and held off the cover to score in the opposite corner, Alvarez this time converting.
Pirates extended their lead on 62 minutes, Patterson crossing for his hat-trick try to make it 22-3.
Knights received a boost on 71 minutes as Joe Sproston went over near enough for Foley to convert, but O’Meara completed the scoring with a close-range try from a long pass by Alvarez.