Stephen Myler kicked five penalties as Northampton made it three wins out of three in the Aviva Premiership by beating Bath 18-14.
But their second away win of the campaign was achieved at the cost of a nasty looking ankle injury to England's Ben Foden in the second half. His replacement, Tom May, wrapped things up with a drop goal four minutes from time.
The only try of the game came after just 70 seconds through Nick Abendanon but Bath were again reliant on the goal-kicking of Olly Barkley, who landed three penalties.
There were only two changes in the home line-up, Paul James coming in at loosehead prop and youngster Ben Williams replacing the injured Matt Banahan at inside centre. Myler was preferred to Ryan Lamb at fly-half for Northampton, while Luther Burrell came into the back line and Tom Mercey joined the front row.
Saints were caught cold after barely a minute. Dan Hipkiss set up a ruck and Bath opened up the blindside for Tom Biggs to slip a deft grubber into the path of Abendanon who scored unopposed in the corner. Barkley was wide with the conversion, his first miss from 15 kicks this season.
A driving maul from the line-out forced a penalty which allowed Myler to kick for Saints on seven minutes but the fly-half's sliced clearance from the restart was not so composed. Bath again used Hipkiss to take the ball up and Barkley slotted the resulting penalty.
Myler again narrowed the deficit to two points with a 35-metre kick on the quarter hour and put his side ahead for the first time with a 21st minute penalty after Ben Skirving infringed at a ruck. Yet another ruck offence by the home team just before the break was punished by Myler with his fourth penalty.
In the second half, Myler added a fifth penalty for a scrum offence but that was quickly cancelled out by Barkley's boot at the other end. When the Saints scrum folded again under pressure from the Bath eight, Barkley was on target from 45 metres on the hour to pull the home side back to 15-14 down.
Barkley missed a chance to regain the lead for bath, while Saints, who has lost Foden to an ankle injury following a man-and-ball tackle by Biggs, nearly grabbed a try when Barkley's clearance was charged down by Samu Manoa, who regathered to feed Tom Wood but the Bath defence scrambled back to deny the England flanker a try.
May then extended the lead to four points with a drop goal, leaving Bath four minutes to find a try to sneak victory but Saints held on and the home side had to be content with a losing bonus point.