Thankfully, Janse van Rensburg was up and walking around during the break, but his absence did not knock Bears out of their stride on their way to a second successive Prem victory this season.
Tom Jordan stretched over to touch down for the third home try soon after the restart and Williams slotted his third kick of the afternoon to make it 22-14.
A third Saints try was then disallowed following an obstruction, and the sniping Randall then bundled over for a converted try near the posts to further extend the home side’s advantage after the Saints defence were sucked in to keep the Bears at bay on the line.
Northampton’s quality in attack, showcased so stylishly in their nine-try mauling of Newcastle last time out, could not be contained for long with two tries in four minutes putting them within eight points of their hosts.
A slick move saw Dingwall feed Hendy, who selflessly teed up Mitchell on the inside to go under the posts and Kemeny’s try put the visitors within eight points.
Bristol showed no signs of panic as their defence held firm impressively to close out a victory sealed with a last-gasp penalty try.
Bristol: Jordan; Rees-Zammit, Janse van Rensburg, Williams, Ibitoye; AJ MacGinty, Randall; Woolmore, Oghre, Kloska, Rubiolo, Batley, Luatua, Grondona, Harding (capt).
Replacements: Gwilliam, Chawatama, Halliwell, Taylor, Owen, Marmion, Pepper Ivanishvili.
Northampton: Freeman; Sleightholme, Hutchinson, Dingwall (capt), Hendy; Smith McParland; Iyogun, Langdon, Kundiona, Coles, Prowse, Kemeny, Taylor, Pollock.
Replacements: Smith, Fischetti, Neculai, Lockett, Chick, Mitchell, Belleau, Pater.
Sin bin: Neculai (74), Freeman (80)
Referee: Ian Tempest
