Bristol trailed all the way through, Northumbria winning a key second period 5-2. The Northumbria lead was cut to 9-8 at the end of the third period but a hat-trick in the final quarter by Sam Smith secured the points.
Earlier, Joel Abbott's six goals led Sheffield to a second win of the day - 11-8 against Exeter. Polytechnic led 3-2 towards the end of the second period against Invicta but were then outplayed. Invicta ran out winners by 11-3, including four goals for Callum Bailey and three from Pat Baker.
Sutton & Cheam came from 6-5 down to beat Penguin 10-8 in the London derby thanks to two goals each in the final period from Stephen Bayles and Alasdair Wakeling.
Picture (Trevor Hyde): GB Olympic goalkeeper Matt Holland, back with his home club Sutton & Cheam this season after playing abroad professionally.