Clarke scores Northampton's third try
Northampton maintained their unbeaten Guinness Premiership home record thanks to tries from Paul Diggin, Ben Foden and Jon Clarke.
Fly-half Stephen Myler also kicked 15 points for the hosts to help them to their fourth victory over Bristol this season, following two wins in the European Challenge Cup and one in the EDF Energy Cup.
But this result will probably hurt most for the visitors, who remain rooted to the foot of the table.
Meanwhile, Northampton stay just clear of the relegation scrap and will surely not be dragged into it with their impressive home form.
The pressure on both clubs was evident in a nervy, disjointed first half where neither side really threatened until Diggin finally struck.
Hooker Dylan Hartley, watched by England scrum coach Graham Rowntree, had a try disallowed when referee Tim Wigglesworth brought him back for a disputed earlier knock-on.
But Bristol were penalised at the resulting scrum and Myler kicked Northampton ahead with a more difficult penalty than the earlier one he had missed.
Three minutes later Diggin produced an excellent burst of speed to exploit weaknesses in the Bristol defence and score the opening try for Northampton.
Scrum-half Lee Dickson fed Foden, preferred at full-back with club captain Bruce Reihana consigned to the bench, and with fast hands released Diggin, who showed a clean pair of heels on his 50 metre dash to the line after centre Luke Eves missed his tackle.
Myler increased the lead to 13-0 with a 37th minute penalty after stand-in skipper Shaun Perry, going for an ambitious interception, was somewhat harshly punished for a deliberate knock-on.
Hartley, up against England's 2007 World Cup hooker Mark Regan, did his international prospects no harm as he attempts a Six Nations challenge to Bath's current England No 1 Lee Mears.
Myler's third penalty, in the 48th minute, put Northampton 16 points clear.
Bristol were caught offside when Scotland winger Sean Lamont took a tap penalty after being the victim of a high tackle by former Wales second row Robert Sidoli, and the former rugby league fly-half confidently booted over the kick from 40-plus metres.
The latest blow seemed to spark the visitors to life and the pressure paid off when Saints conceded a penalty in front of their own posts and Barnes finally opened Bristol's account in the 50th minute.
They spurned a penalty opportunity in favour of a lineout in the corner before replacement Nathan Brew - brother of Neil - was held up inches short of the line, but an infringement at the resulting ruck cost Bristol their momentum.
Saints retaliated to wrap up the match when Foden broke through three tackles on a tremendous 40-metre diagonal run through the Bristol defence to touch down near the posts in the 73rd minute, with Myler converting.
They struck again in the final minute when poor defending allowed centre Clarke in for their third try, with Myler again adding the kick.
With seconds remaining, impressive Bristol left-wing David Lemi kicked ahead and won the chase for a consolation try for the visitors.

England 9-18 Australia - Highlights
Harlequins 15-15 Llanelli - Davies
Harlequins 15-15 Llanelli - Robshaw
Harlequins 15-15 Llanelli - Owens
England 9-18 Australia - Wilkinson & Moody
England 9-18 Australia - Johnson
England 9-18 Australia - Giteau
England 9-18 Australia - Genia & Ashley-Cooper
| Time | Fixture |
|---|---|
| Guinness Premiership | |
| Friday 20th November | |
| Guinness Premiership | |
| 19:45 | Gloucester vs Leicester |
| 20:00 | Worcester vs Bath |
| Saturday 21st November | |
| 13:00 | Northampton vs Harlequins |
| Sunday 22nd November | |
| 15:00 | London Irish vs Newcastle |
| 15:00 | Saracens vs Wasps |
| 15:00 | Leeds Carnegie vs Sale |
| Friday 27th November | |
| 19:45 | Sale vs Wasps |
| 20:00 | Newcastle vs Northampton |
| 20:00 | Worcester vs Saracens |
| Saturday 28th November | |
| 15:00 | Harlequins vs Gloucester |
| 15:00 | Worcester vs Saracens |
| 15:00 | Leicester vs Leeds Carnegie |
| 17:35 | Bath vs London Irish |
| Saturday 5th December | |
| 15:00 | London Irish vs Worcester |
| 15:00 | Northampton vs Bath |
| 15:00 | Gloucester vs Newcastle |
| 17:35 | Saracens vs Sale |
| Sunday 6th December | |
| 15:00 | Wasps vs Leicester |
| 15:00 | Leeds Carnegie vs Harlequins |
| Saturday 26th December | |
| 14:15 | Bath vs Gloucester |
| 15:00 | Leicester vs Sale |
| 15:00 | Worcester vs Northampton |
| Sunday 27th December | |
| 15:00 | London Irish vs Saracens |
| 15:00 | Newcastle vs Leeds Carnegie |
| 16:00 | Harlequins vs Wasps |
| Result |
|---|
| Guinness Premiership |
| Sunday 1st November |
| Guinness Premiership |
| Newcastle 14 - 3 Worcester |
| Wasps 9 - 15 Leeds Carnegie |
| Saturday 31st October |
| Leicester 29 - 15 Northampton |
| Harlequins 9 - 9 London Irish |
| Bath 11 - 12 Saracens |
| Friday 30th October |
| Sale 28 - 23 Gloucester |
| Sunday 25th October |
| Saracens 21 - 15 Leeds Carnegie |
| Saturday 24th October |
| Gloucester 6 - 35 Wasps |
| London Irish 18 - 12 Leicester |
| Northampton 21 - 16 Sale |
| Worcester 22 - 26 Harlequins |
| Bath 16 - 27 Newcastle |
| Sunday 4th October |
| Leeds Carnegie 10 - 26 Gloucester |
| Wasps 20 - 15 Northampton |
| Newcastle 15 - 22 Saracens |
| Saturday 3rd October |
| Harlequins 13 - 11 Bath |
| Leicester 19 - 14 Worcester |
| Friday 2nd October |
| Sale 8 - 11 London Irish |
| Sunday 27th September |
| Saracens 19 - 16 Gloucester |
| London Irish 28 - 16 Wasps |
| Saturday 26th September |
| Bath 20 - 20 Leicester |
| Worcester 24 - 18 Sale |
| Northampton 30 - 10 Leeds Carnegie |
| Friday 25th September |
| Newcastle 17 - 17 Harlequins |
| Sunday 20th September |
| Wasps 23 - 3 Worcester |
Jonny Wilkinson told The Rugby Club he hopes to play with new-found freedom against Australia on Saturday.
Aussie Matt Giteau tells Rugby Club that he is keen to avoid a repeat of his first Twickenham outing.
Back Nikolai Valuev, Didier Drogba and Jonny Wilkinson this weekend, says Ed Chamberlin.
France have named a heavy back row in a bid to counter the might of the South Africa ahead of the Test match in Toulouse on Friday night.
Dan Carter's disciplinary hearing has been put back to Tuesday at the request of the New Zealand team management.
Cardiff Blues won their LV= Cup clash against Gloucester thanks to a last-gasp penalty from Ceri Sweeney at Kingsholm.
Harlequins and Scarlets shared the spoils following a tremendous battle in their LV= clash at the Twickenham Stoop.
Wasps withstood some late pressure to earn a hard-fought 24-20 LV= Cup triumph over London Irish.