Robbie Kydd created one superb try and scored another as Northampton brought Bath back down to earth with a bump at Franklin’s Gardens.
The full-back is only in the Saints side thanks to Bruce Reihana’s move to centre but enhanced his claims for a place in the Scotland squad this autumn with his energetic all-round display.
Northampton’s first three tries came from their Scottish contingent, prop Tom Smith rumbling over before Kydd set up wing Sean Lamont and then claimed a first Premiership score of his own, prior to Carlos Spencer clinching the bonus point.
Reihana added three penalties and three conversions while Bath were a shadow of the side that had destroyed Leicester at The Rec a week ago.
Andy Higgins and Michael Stephenson claimed their tries with Olly Barkley adding a conversion and two penalties.
For the most part they were second best all over the pitch as a well organised defence kept their backs at bay.
Bath had been forced into a handful of changes after the 43-25 win over the Tigers, with Feaunati taking over the captaincy from the injured Steve Borthwick and Rob Fidler starting at lock.
Northampton recalled lock Matt Lord to make his 100th appearance for the club and the virus that had laid several players low eased to allow Ben Cohen and Steve Thompson to return.
These sides produced a minor classic at the end of last season when Reihana’s two tries and Mark Easter’s late score inspired the Saints to a 24-21 victory to extend Bath’s winless run at Franklin’s Gardens to six years.
The free-flowing stuff was in short supply early on in this game as Bath kicked possession away and gave away penalties for Reihana to put Saints 9-3 up at the end of the first quarter.
Northampton, though, were more effective in the scrum – courtesy of England prospect Pat Barnard’s effectiveness at tight-head – and sharper on the floor.
Bath suffered a setback in that area when open-side flanker Gareth Delve was forced off after 15 minutes with a shoulder injury – and another blow when captain Feaunati was sin-binned for killing a ruck.
The Samoan number eight was off the field when Lamont’s break down the right set up the position for a line-out with Smith driven over from close range in the 25th minute.
Feaunati returned, only for his side to concede a second try two minutes before the break, thanks to a sublime piece of skill from Kydd who is finally making progress after two years of injury problems following his move from Saracens.
The 24-year-old’s burst down the right was followed by a brilliant pass out of the back of his right hand to Lamont, who cruised over for his third try of the season, with Reihana converting from the touchline.
Bath rallied briefly when Barkley’s cross-kick was batted back in-field by Feaunati on the right.
Higgins strolled over and centre Barkley’s conversion, followed by a penalty early in the second half, briefly hauled them back into the game.
Spencer put an end to the revival, though, when he injected pace and flair into a move which appeared to be going nowhere on a 30-metre broken-field run that set up Kydd to break a tackle and stretch over and score.
The New Zealand fly-half heaped more embarrassment on the visitors when scored under the posts after Reihana had created the opening with another dazzling run 10 minutes from time.
Replacement wing Stephenson capped a long spell of Bath pressure with a try in the corner five minutes from time but they were well beaten by the time he claimed the consolation score.
To add to their misery Danny Grewcock was shown the yellow card by referee Wayne Barnes for impeding Cohen as Northampton attempted to break away in the final move of the match.