|Bath (0) 11|
|Try: Rokoduguni Pens: Ford 2|
|Northampton (3) 13|
|Try: Burrell Con: Hanrahan Pens: Hanrahan 2|
|Relive Saturday's Premiership action|
JJ Hanrahan's late penalty saw Northampton earn a narrow win at Bath after an error-strewn, scrappy game.
The Saints led 3-0 after the break through a Hanrahan penalty, with Bath's scrum punished several times during a disappointing first period.
George Ford levelled with a penalty before his pass was intercepted by Luther Burrell for the opening try.
Another Ford penalty and a fine Semesa Rokoduguni try put Bath ahead but Hanrahan's 73rd-minute penalty won it.
It was a fourth defeat for last season's Premiership finalists as their disappointing campaign continues, and it was Northampton's dominance in the scrum that made the difference.
The first points came 24 minutes into the game and through the boot of Hanrahan. Bath soon conceded yet another penalty from a scrum and prop Henry Thomas was sent to the sin-bin as a result - their eighth yellow card of the season.
Northampton came close to adding to their lead shortly before the break but made a mess of the grounding with the try-line at their mercy and half-time came with the score at 3-0.
Bath levelled through the boot of Ford, but it was his mistake that led to Northampton's try as, after a moment of rare indecision, his pass was intercepted by Burrell who had a clear run to the line.
Hanrahan sent over the conversion but Ford soon reduced Bath's deficit to 10-6 with a penalty.
Veteran South Africa forward Victor Matfield came off the bench for his second Northampton appearance before a moment of magic from Rokoduguni lit the game up as he flew down the right wing, bursting through the tackle of Ben Foden before handing off George North to touch down in the corner for 11-10.
Hanrahan kicked a penalty from just inside Bath's half to put Saints back in front with seven minutes remaining after another illegal scrum and the visitors held on for victory.
Bath head coach Mike Ford told BBC Sport:
"On a scale of one to 10 in terms of frustration, it's 10 out of 10.
"The points that were given we had control, the try interception from George's pass, the last penalty was our scrum feed. The second thing I'm frustrated about is scrums, it's just a lottery.
"Today, flip a coin. We've got referees, refereeing and they don't know what is going on. It's ruining the game, they are deciding who is winning games. We need to fix scrums.
"We are not playing good enough, we are better than that. We'll take our medicine. We had lot of disruption in pre-season. Teams are coming to stop us, we are not taking our chances and when you don't win confidence suffers."
Northampton director of rugby Jim Mallinder told BBC Sport:
"We were pleased to go in 3-0 up. Second half, credit to Bath, they defended well and played as they can and then at the end we took our opportunity.
"You feel when Rokoduguni went over the momentum had shifted. But when you are only a few points behind you know you are always in the game and credit to our lads for sticking in there.
"We think Courtney Lawes will be back for next week. Dylan Hartley and Tom Wood we're not sure, we're hopeful for those. Wood's got a shoulder injury, Hartley is recovering from his concussion."
Bath: Watson; Rokoduguni, Joseph, Devoto, Banahan; Ford, Cook; Auterac, Webber, Thomas, Ewels, Ellis, Garvey, Louw (capt), Houston.
Replacements: Batty, Lahiff, Wilson, Denton, Mercer, Matawalu, Priestland, Homer.
Sin-bin: Thomas (35)
Northampton: Foden (capt); Elliott, G. Pisi, Burrell, North; Hanrahan, Fotuali'i; E. Waller, Haywood, Brookes, Paterson, Day, Gibson, Harrison, Dickinson.
Replacements: Marshall, A. Waller, Hill, Matfield, Craig, Dickson, Myler, K. Pisi.
Referee: Craig Maxwell-Keys.
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