The Drovers went into Saturday’s clash at Church Bank top of Pool 8 but the away side’s 13-16 win means the two teams are now level on 10 points at the top of the pool.
A Jake Randall try, converted by Cerith Rees gave the home side a fast start inside three minutes but the English side came back to lead at half time. James Lennard kicked a penalty and converted Andrew Symons’ try as the Knights turned the tables to go in with a 10-7 lead.
Both sides’ kickers went head to head in the second half, Lennard and Rees slotting two penalties apiece but it was Doncaster who went home with the points.
At Rodney Parade, Newcastle confirmed themselves as one of the favourites for the competition with a 10-26 win over Newport.
No. 8 Craig Everett crossed for the Black and Ambers in a hugely committed performance and while Scott Sneddon kept his side in touch, the runaway leaders of the English Championship ground out the win.
In Pool 2, Bedwas made sure their long trip north to take on Stirling was worthwhile as they came back with their first cup win of the season.
They edged out the Scottish side 22-32 with Rory Budina and Ross Wardle among their five try scorers.
In Pool 3, Carmarthen Quins made sure they kept up the pressure on the Cornish Pirates with a 20-17 home win over Dundee. Sadly for them though, the Pirates were convincing winners at home to Swansea in the other game in the pool.
Elsewhere, Aberavon matched Plymouth in the try scoring stakes, both sides crossing twice but the Wizards were unable to hold out for the win as the English side sneaked a 20-21 win in Pool 7.
